Merge remote-tracking branch 'origin/dev' into 5.13

Conflicts:
	src/core/content_browser_client_qt.cpp
	src/core/content_browser_client_qt.h

Change-Id: I3da791a82dab56fd7535ba1e4c0ab1d9ca74f547

74 files changed, 4495 insertions, 106 deletions

diff --git a/configure.pri b/configure.pri
index 26c57ce61..46fec536a 100644
--- a/configure.pri
+++ b/configure.pri
@@ -312,3 +312,8 @@ defineTest(qtConfTest_hasThumbFlag) {
     # no flag assume mthumb
     return(true)
 }
+
+defineTest(qtConfTest_hasGcc6OrNewer) {
+    greaterThan(QT_GCC_MAJOR_VERSION, 5):return(true)
+    return(false)
+}
diff --git a/src/3rdparty b/src/3rdparty
-Subproject c677809fe785df63fe97608cb5a949302b2f0c6
+Subproject 5a76a0a325a041dab3c93943c99835d3e929762
diff --git a/src/core/browser_main_parts_qt.cpp b/src/core/browser_main_parts_qt.cpp
index cfe9ea8bb..e6c76fb4f 100644
--- a/src/core/browser_main_parts_qt.cpp
+++ b/src/core/browser_main_parts_qt.cpp
@@ -44,7 +44,16 @@
 #include "base/threading/thread_restrictions.h"
 #include "content/public/browser/browser_main_parts.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/child_process_security_policy.h"
 #include "content/public/common/service_manager_connection.h"
+#include "extensions/buildflags/buildflags.h"
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/common/constants.h"
+#include "extensions/common/extensions_client.h"
+#include "extensions/extensions_browser_client_qt.h"
+#include "extensions/extension_system_factory_qt.h"
+#include "common/extensions/extensions_client_qt.h"
+#endif //BUILDFLAG(ENABLE_EXTENSIONS)
 #include "services/resource_coordinator/public/cpp/process_resource_coordinator.h"
 #include "services/resource_coordinator/public/cpp/resource_coordinator_features.h"
 #include "services/service_manager/public/cpp/connector.h"
@@ -247,6 +256,9 @@ BrowserMainPartsQt::~BrowserMainPartsQt() = default;
 
 int BrowserMainPartsQt::PreEarlyInitialization()
 {
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    content::ChildProcessSecurityPolicy::GetInstance()->RegisterWebSafeScheme(extensions::kExtensionScheme);
+#endif //ENABLE_EXTENSIONS
     base::MessageLoop::InitMessagePumpForUIFactory(messagePumpFactory);
     return 0;
 }
@@ -255,6 +267,15 @@ void BrowserMainPartsQt::PreMainMessageLoopStart()
 {
 }
 
+void BrowserMainPartsQt::PreMainMessageLoopRun()
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionsClient::Set(new extensions::ExtensionsClientQt());
+    extensions::ExtensionsBrowserClient::Set(new extensions::ExtensionsBrowserClientQt());
+    extensions::ExtensionSystemFactoryQt::GetInstance();
+#endif //ENABLE_EXTENSIONS
+}
+
 void BrowserMainPartsQt::PostMainMessageLoopRun()
 {
     // The ProfileQt's destructor uses the MessageLoop so it should be deleted
diff --git a/src/core/browser_main_parts_qt.h b/src/core/browser_main_parts_qt.h
index 04ca9483d..374220c3b 100644
--- a/src/core/browser_main_parts_qt.h
+++ b/src/core/browser_main_parts_qt.h
@@ -66,6 +66,7 @@ public:
 
     int PreEarlyInitialization() override;
     void PreMainMessageLoopStart() override;
+    void PreMainMessageLoopRun() override;
     void PostMainMessageLoopRun() override;
     int PreCreateThreads() override;
     void ServiceManagerConnectionStarted(content::ServiceManagerConnection *connection) override;
diff --git a/src/core/common/extensions/api/qtwebengine_extensions_features.gni b/src/core/common/extensions/api/qtwebengine_extensions_features.gni
new file mode 100644
index 000000000..ed7e713c6
--- /dev/null
+++ b/src/core/common/extensions/api/qtwebengine_extensions_features.gni
@@ -0,0 +1,25 @@
+import("//tools/json_schema_compiler/json_features.gni")
+
+json_features("qt_api_features") {
+  feature_type = "APIFeature"
+  method_name = "AddQtAPIFeatures"
+  sources = [
+    "//extensions/common/api/_webengine_api_features.json"
+  ]
+}
+
+json_features("qt_permission_features") {
+  feature_type = "PermissionFeature"
+  method_name = "AddQtPermissionFeatures"
+  sources = [
+    "//extensions/common/api/_permission_features.json"
+  ]
+}
+
+group("qtwebengine_extensions_features") {
+  public_deps = [
+    ":qt_api_features",
+    ":qt_permission_features",
+    "//extensions/common/api:extensions_features",
+  ]
+}
diff --git a/src/core/common/extensions/extensions_api_provider_qt.cpp b/src/core/common/extensions/extensions_api_provider_qt.cpp
new file mode 100644
index 000000000..aa746133e
--- /dev/null
+++ b/src/core/common/extensions/extensions_api_provider_qt.cpp
@@ -0,0 +1,105 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "extensions_api_provider_qt.h"
+
+#include "chrome/grit/common_resources.h"
+
+#include "extensions/common/api/api_features.h"
+#include "extensions/common/api/behavior_features.h"
+#include "extensions/common/api/generated_schemas.h"
+#include "extensions/common/api/manifest_features.h"
+#include "extensions/common/api/permission_features.h"
+#include "extensions/common/common_manifest_handlers.h"
+#include "extensions/common/features/feature_provider.h"
+#include "extensions/common/features/json_feature_provider_source.h"
+#include "extensions/common/permissions/permissions_info.h"
+#include "extensions/grit/extensions_resources.h"
+
+#include "qt_api_features.h"
+//#include "qt_behavior_features.h"
+#include "qt_permission_features.h"
+//#include "qt_manifest_features.h"
+
+
+namespace extensions {
+
+ExtensionsAPIProviderQt::ExtensionsAPIProviderQt()
+{
+
+}
+
+void ExtensionsAPIProviderQt::RegisterManifestHandlers()
+{
+    RegisterCommonManifestHandlers();
+}
+
+void ExtensionsAPIProviderQt::AddAPIFeatures(FeatureProvider *provider)
+{
+    AddCoreAPIFeatures(provider);
+    AddQtAPIFeatures(provider);
+}
+
+void ExtensionsAPIProviderQt::AddAPIJSONSources(JSONFeatureProviderSource *json_source)
+{
+    json_source->LoadJSON(IDR_EXTENSION_API_FEATURES);
+    json_source->LoadJSON(IDR_CHROME_EXTENSION_API_FEATURES);
+}
+
+void ExtensionsAPIProviderQt::AddPermissionFeatures(FeatureProvider *provider)
+{
+    AddQtPermissionFeatures(provider);
+}
+
+bool ExtensionsAPIProviderQt::IsAPISchemaGenerated(const std::string &name)
+{
+    return api::GeneratedSchemas::IsGenerated(name);
+}
+
+base::StringPiece ExtensionsAPIProviderQt::GetAPISchema(const std::string &name)
+{
+    return api::GeneratedSchemas::Get(name);
+}
+
+void ExtensionsAPIProviderQt::RegisterPermissions(PermissionsInfo* permissions_info)
+{
+
+}
+
+}
diff --git a/src/core/common/extensions/extensions_api_provider_qt.h b/src/core/common/extensions/extensions_api_provider_qt.h
new file mode 100644
index 000000000..8b85e5de2
--- /dev/null
+++ b/src/core/common/extensions/extensions_api_provider_qt.h
@@ -0,0 +1,75 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#ifndef EXTENSIONS_API_PROVIDER_QT_H
+#define EXTENSIONS_API_PROVIDER_QT_H
+
+#include "extensions/common/extensions_api_provider.h"
+
+#include "base/macros.h"
+
+namespace extensions {
+
+class ExtensionsAPIProviderQt : public ExtensionsAPIProvider
+{
+public:
+    ExtensionsAPIProviderQt();
+
+    void RegisterManifestHandlers() override;
+    void AddAPIFeatures(FeatureProvider *provider) override;
+    void AddAPIJSONSources(JSONFeatureProviderSource* json_source) override;
+    void AddPermissionFeatures(FeatureProvider* provider) override;
+
+    bool IsAPISchemaGenerated(const std::string& name) override;
+    base::StringPiece GetAPISchema(const std::string& name) override;
+
+
+    // Adds feature definitions to the given |provider| of the specified type.
+    void AddManifestFeatures(FeatureProvider* provider) override { }
+    void AddBehaviorFeatures(FeatureProvider* provider) override { }
+
+
+    // Registers permissions for any associated API features.
+    void RegisterPermissions(PermissionsInfo* permissions_info) override;
+
+DISALLOW_COPY_AND_ASSIGN(ExtensionsAPIProviderQt);
+};
+
+}
+
+#endif // EXTENSIONS_API_PROVIDER_QT_H
diff --git a/src/core/common/extensions/extensions_client_qt.cpp b/src/core/common/extensions/extensions_client_qt.cpp
new file mode 100644
index 000000000..6c6200eb0
--- /dev/null
+++ b/src/core/common/extensions/extensions_client_qt.cpp
@@ -0,0 +1,190 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions_client_qt.h"
+
+#include "extensions/common/alias.h"
+#include "extensions/common/core_extensions_api_provider.h"
+#include "extensions/common/extension_urls.h"
+
+#include "extensions/common/features/simple_feature.h"
+#include "extensions/common/permissions/permissions_info.h"
+
+#include "extensions_api_provider_qt.h"
+
+
+namespace extensions {
+
+template<class FeatureClass> SimpleFeature *CreateFeature()
+{
+    return new FeatureClass;
+}
+
+static base::LazyInstance<ExtensionsClientQt>::Leaky g_client = LAZY_INSTANCE_INITIALIZER;
+
+ExtensionsClientQt *ExtensionsClientQt::GetInstance()
+{
+    return g_client.Pointer();
+}
+
+ExtensionsClientQt::ExtensionsClientQt() : ExtensionsClient()
+{
+    AddAPIProvider(std::make_unique<CoreExtensionsAPIProvider>());
+    AddAPIProvider(std::make_unique<ExtensionsAPIProviderQt>());
+}
+
+// Initializes global state. Not done in the constructor because unit tests
+// can create additional ExtensionsClients because the utility thread runs
+// in-process.
+void ExtensionsClientQt::Initialize()
+{
+}
+
+void ExtensionsClientQt::InitializeWebStoreUrls(base::CommandLine *command_line)
+{
+}
+
+// Returns the global PermissionMessageProvider to use to provide permission
+// warning strings.
+const PermissionMessageProvider &ExtensionsClientQt::GetPermissionMessageProvider() const
+{
+    return permission_message_provider_;
+}
+
+// Returns the application name. For example, "Chromium" or "app_shell".
+const std::string ExtensionsClientQt::GetProductName()
+{
+    return "Qt WebEngine"; // return Qt WebEngine for now, consider returning the application name if possible.
+}
+
+// Takes the list of all hosts and filters out those with special
+// permission strings. Adds the regular hosts to |new_hosts|,
+// and adds any additional permissions to |permissions|.
+// TODO(sashab): Split this function in two: One to filter out ignored host
+// permissions, and one to get permissions for the given hosts.
+void ExtensionsClientQt::FilterHostPermissions(const URLPatternSet &hosts,
+                                               URLPatternSet *new_hosts,
+                                               PermissionIDSet *permissions) const
+{
+}
+
+// Replaces the scripting whitelist with |whitelist|. Used in the renderer{}
+// only used for testing in the browser process.
+void ExtensionsClientQt::SetScriptingWhitelist(const ExtensionsClient::ScriptingWhitelist &whitelist)
+{
+    scripting_whitelist_ = whitelist;
+}
+
+// Return the whitelist of extensions that can run content scripts on
+// any origin.
+const ExtensionsClient::ScriptingWhitelist &ExtensionsClientQt::GetScriptingWhitelist() const
+{
+    return scripting_whitelist_;
+}
+
+// Get the set of chrome:// hosts that |extension| can run content scripts on.
+URLPatternSet ExtensionsClientQt::GetPermittedChromeSchemeHosts(const Extension *extension,
+                                                                const APIPermissionSet &api_permissions) const
+{
+    return URLPatternSet();
+}
+
+// Returns false if content scripts are forbidden from running on |url|.
+bool ExtensionsClientQt::IsScriptableURL(const GURL &url, std::string *error) const
+{
+    return true;
+}
+
+// Determines if certain fatal extensions errors should be surpressed
+// (i.e., only logged) or allowed (i.e., logged before crashing).
+bool ExtensionsClientQt::ShouldSuppressFatalErrors() const
+{
+    return true;
+}
+
+// Records that a fatal error was caught and suppressed. It is expected that
+// embedders will only do so if ShouldSuppressFatalErrors at some point
+// returned true.
+void ExtensionsClientQt::RecordDidSuppressFatalError()
+{
+}
+
+// Returns the base webstore URL prefix.
+const GURL &ExtensionsClientQt::GetWebstoreBaseURL() const
+{
+    if (base_url_.is_empty())
+        base_url_ = GURL(extension_urls::kChromeWebstoreBaseURL);
+    return base_url_;
+}
+
+// Returns the URL to use for update manifest queries.
+const GURL &ExtensionsClientQt::GetWebstoreUpdateURL() const
+{
+    if (update_url_.is_empty())
+        update_url_ = GURL(extension_urls::GetWebstoreUpdateUrl());
+    return update_url_;
+}
+
+// Returns a flag indicating whether or not a given URL is a valid
+// extension blacklist URL.
+bool ExtensionsClientQt::IsBlacklistUpdateURL(const GURL &url) const
+{
+    return true;
+}
+
+// Returns the set of file paths corresponding to any images within an
+// extension's contents that may be displayed directly within the browser UI
+// or WebUI, such as icons or theme images. This set of paths is used by the
+// extension unpacker to determine which assets should be transcoded safely
+// within the utility sandbox.
+//
+// The default implementation returns the images used as icons for the
+// extension itself, so implementors of ExtensionsClient overriding this may
+// want to call the base class version and then add additional paths to that
+// result.
+std::set<base::FilePath> ExtensionsClientQt::GetBrowserImagePaths(const Extension *extension)
+{
+    return ExtensionsClient::GetBrowserImagePaths(extension);
+}
+
+} // namespace extensions
diff --git a/src/core/common/extensions/extensions_client_qt.h b/src/core/common/extensions/extensions_client_qt.h
new file mode 100644
index 000000000..657487277
--- /dev/null
+++ b/src/core/common/extensions/extensions_client_qt.h
@@ -0,0 +1,148 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXTENSIONS_CLIENT_QT_H
+#define EXTENSIONS_CLIENT_QT_H
+
+#include "extensions/common/extensions_client.h"
+
+#include "base/compiler_specific.h"
+#include "base/lazy_instance.h"
+#include "base/macros.h"
+#include "chrome/common/extensions/permissions/chrome_permission_message_provider.h"
+#include "extensions/common/features/feature_provider.h"
+#include "extensions/common/features/json_feature_provider_source.h"
+#include "extensions/common/permissions/extensions_api_permissions.h"
+#include "url/gurl.h"
+
+namespace extensions {
+
+// Sets up global state for the extensions system. Should be Set() once in each
+// process. This should be implemented by the client of the extensions system.
+class ExtensionsClientQt : public ExtensionsClient
+{
+public:
+    ExtensionsClientQt();
+    virtual ~ExtensionsClientQt() {}
+
+    // Initializes global state. Not done in the constructor because unit tests
+    // can create additional ExtensionsClients because the utility thread runs
+    // in-process.
+    void Initialize() override;
+    void InitializeWebStoreUrls(base::CommandLine *command_line) override;
+
+    // Returns the global PermissionMessageProvider to use to provide permission
+    // warning strings.
+    const PermissionMessageProvider &GetPermissionMessageProvider() const override;
+
+    // Returns the application name. For example, "Chromium" or "app_shell".
+    const std::string GetProductName() override;
+
+    // Takes the list of all hosts and filters out those with special
+    // permission strings. Adds the regular hosts to |new_hosts|,
+    // and adds any additional permissions to |permissions|.
+    // TODO(sashab): Split this function in two: One to filter out ignored host
+    // permissions, and one to get permissions for the given hosts.
+    void FilterHostPermissions(const URLPatternSet &hosts,
+                               URLPatternSet *new_hosts,
+                               PermissionIDSet *permissions) const override;
+
+    // Replaces the scripting whitelist with |whitelist|. Used in the renderer;
+    // only used for testing in the browser process.
+    void SetScriptingWhitelist(const ScriptingWhitelist &whitelist) override;
+
+    // Return the whitelist of extensions that can run content scripts on
+    // any origin.
+    const ScriptingWhitelist &GetScriptingWhitelist() const override;
+
+    // Get the set of chrome:// hosts that |extension| can run content scripts on.
+    URLPatternSet GetPermittedChromeSchemeHosts(const Extension *extension,
+                                                const APIPermissionSet &api_permissions) const override;
+
+    // Returns false if content scripts are forbidden from running on |url|.
+    bool IsScriptableURL(const GURL &url, std::string *error) const override;
+
+    // Determines if certain fatal extensions errors should be surpressed
+    // (i.e., only logged) or allowed (i.e., logged before crashing).
+    bool ShouldSuppressFatalErrors() const override;
+
+    // Records that a fatal error was caught and suppressed. It is expected that
+    // embedders will only do so if ShouldSuppressFatalErrors at some point
+    // returned true.
+    void RecordDidSuppressFatalError() override;
+
+    // Returns the base webstore URL prefix.
+    const GURL &GetWebstoreBaseURL() const override;
+
+    // Returns the URL to use for update manifest queries.
+    const GURL &GetWebstoreUpdateURL() const override;
+
+    // Returns a flag indicating whether or not a given URL is a valid
+    // extension blacklist URL.
+    bool IsBlacklistUpdateURL(const GURL &url) const override;
+
+    // Returns the set of file paths corresponding to any images within an
+    // extension's contents that may be displayed directly within the browser UI
+    // or WebUI, such as icons or theme images. This set of paths is used by the
+    // extension unpacker to determine which assets should be transcoded safely
+    // within the utility sandbox.
+    //
+    // The default implementation returns the images used as icons for the
+    // extension itself, so implementors of ExtensionsClient overriding this may
+    // want to call the base class version and then add additional paths to that
+    // result.
+    std::set<base::FilePath> GetBrowserImagePaths(const Extension *extension) override;
+    // Get the LazyInstance for ChromeExtensionsClient.
+    static ExtensionsClientQt *GetInstance();
+
+private:
+    ScriptingWhitelist scripting_whitelist_;
+    const ChromePermissionMessageProvider permission_message_provider_;
+    mutable GURL update_url_;
+    mutable GURL base_url_;
+    DISALLOW_COPY_AND_ASSIGN(ExtensionsClientQt);
+};
+
+} // namespace extensions
+
+#endif // EXTENSIONS_CLIENT_QT_H
diff --git a/src/core/config/common.pri b/src/core/config/common.pri
index be57942d2..57913423a 100644
--- a/src/core/config/common.pri
+++ b/src/core/config/common.pri
@@ -22,7 +22,10 @@ gn_args += \
     use_custom_libcxx=false \
     v8_use_external_startup_data=false \
     toolkit_views=false \
-    treat_warnings_as_errors=false
+    treat_warnings_as_errors=false \
+    safe_browsing_mode=0 \
+    optimize_webui=false \
+    closure_compile=false
 
 !win32: gn_args += \
     use_jumbo_build=true \
@@ -57,6 +60,12 @@ qtConfig(webengine-webrtc) {
 
 qtConfig(webengine-proprietary-codecs): gn_args += proprietary_codecs=true ffmpeg_branding=\"Chrome\"
 
+qtConfig(webengine-extensions) {
+    gn_args += enable_extensions=true
+} else {
+    gn_args += enable_extensions=false
+}
+
 precompile_header {
     gn_args += enable_precompiled_headers=true
 } else {
diff --git a/src/core/configure.json b/src/core/configure.json
index 755a525a8..f111247e4 100644
--- a/src/core/configure.json
+++ b/src/core/configure.json
@@ -20,6 +20,7 @@
             "webengine-pulseaudio": "boolean",
             "webengine-spellchecker": "boolean",
             "webengine-native-spellchecker": "boolean",
+            "webengine-extensions": "boolean",
             "webengine-webrtc": "boolean",
             "webengine-geolocation": "boolean",
             "webengine-v8-snapshot": "boolean",
@@ -36,6 +37,7 @@
             "printing-and-pdf": { "type": "boolean", "name": "webengine-printing-and-pdf" },
             "proprietary-codecs": { "type": "boolean", "name": "webengine-proprietary-codecs" },
             "spellchecker": { "type": "boolean", "name": "webengine-spellchecker" },
+            "extensions": { "type": "boolean", "name": "webengine-extensions" },
             "webrtc": { "type": "boolean", "name": "webengine-webrtc" }
         }
     },
@@ -328,6 +330,10 @@
         "webengine-arm-thumb" : {
             "label": "thumb instruction set",
             "type": "hasThumbFlag"
+        },
+        "webengine-extensions-gcc-version" : {
+            "label": "GCC 6 or newer",
+            "type": "hasGcc6OrNewer"
         }
     },
 
@@ -548,6 +554,14 @@
             "condition": "config.macos && features.webengine-spellchecker",
             "output": [ "publicFeature" ]
         },
+        "webengine-extensions": {
+            "label": "Extensions",
+            "purpose": "Enables Chromium extensions within certain limits. Currently used for enabling the pdf viewer.",
+            "section": "WebEngine",
+            "condition": "features.webengine-printing-and-pdf && (tests.webengine-extensions-gcc-version || config.clang || !config.gcc)",
+            "autoDetect": "features.webengine-printing-and-pdf",
+            "output": [ "publicFeature" ]
+        },
         "webengine-webrtc": {
             "label": "WebRTC",
             "purpose": "Provides WebRTC support.",
@@ -727,6 +741,7 @@
                 "webengine-webchannel",
                 "webengine-v8-snapshot",
                 "webengine-kerberos",
+                "webengine-extensions",
                 {
                     "type": "feature",
                     "args": "webengine-v8-snapshot-support",
diff --git a/src/core/content_browser_client_qt.cpp b/src/core/content_browser_client_qt.cpp
index 095528244..3861d1c95 100644
--- a/src/core/content_browser_client_qt.cpp
+++ b/src/core/content_browser_client_qt.cpp
@@ -48,6 +48,7 @@
 #if QT_CONFIG(webengine_spellchecker)
 #include "chrome/browser/spellchecker/spell_check_host_chrome_impl.h"
 #endif
+#include "components/guest_view/browser/guest_view_base.h"
 #include "components/network_hints/browser/network_hints_message_filter.h"
 #include "content/browser/renderer_host/render_view_host_delegate.h"
 #include "content/common/url_schemes.h"
@@ -70,6 +71,7 @@
 #include "content/public/common/service_names.mojom.h"
 #include "content/public/common/url_constants.h"
 #include "media/media_buildflags.h"
+#include "extensions/buildflags/buildflags.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "printing/buildflags/buildflags.h"
@@ -128,6 +130,16 @@
 #include "location_provider_qt.h"
 #endif
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/extensions_browser_client_qt.h"
+#include "extensions/browser/extension_message_filter.h"
+#include "extensions/browser/guest_view/extensions_guest_view_message_filter.h"
+#include "extensions/browser/io_thread_extension_message_filter.h"
+#include "extensions/common/constants.h"
+#include "common/extensions/extensions_client_qt.h"
+#include "renderer_host/resource_dispatcher_host_delegate_qt.h"
+#endif
+
 #include <QGuiApplication>
 #include <QLocale>
 #ifndef QT_NO_OPENGL
@@ -252,6 +264,11 @@ void ContentBrowserClientQt::RenderProcessWillLaunch(content::RenderProcessHost*
 #if QT_CONFIG(webengine_printing_and_pdf)
     host->AddFilter(new PrintingMessageFilterQt(host->GetID()));
 #endif
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    host->AddFilter(new extensions::ExtensionMessageFilter(host->GetID(), host->GetBrowserContext()));
+    host->AddFilter(new extensions::IOThreadExtensionMessageFilter(host->GetID(), host->GetBrowserContext()));
+    host->AddFilter(new extensions::ExtensionsGuestViewMessageFilter(host->GetID(), host->GetBrowserContext()));
+#endif //ENABLE_EXTENSIONS
 
     service_manager::mojom::ServicePtr service;
     *service_request = mojo::MakeRequest(&service);
@@ -266,7 +283,11 @@ void ContentBrowserClientQt::RenderProcessWillLaunch(content::RenderProcessHost*
 
 void ContentBrowserClientQt::ResourceDispatcherHostCreated()
 {
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    m_resourceDispatcherHostDelegate.reset(new ResourceDispatcherHostDelegateQt);
+#else
     m_resourceDispatcherHostDelegate.reset(new content::ResourceDispatcherHostDelegate);
+#endif
     content::ResourceDispatcherHost::Get()->SetDelegate(m_resourceDispatcherHostDelegate.get());
 }
 
@@ -285,6 +306,10 @@ content::MediaObserver *ContentBrowserClientQt::GetMediaObserver()
 void ContentBrowserClientQt::OverrideWebkitPrefs(content::RenderViewHost *rvh, content::WebPreferences *web_prefs)
 {
     if (content::WebContents *webContents = rvh->GetDelegate()->GetAsWebContents()) {
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+        if (guest_view::GuestViewBase::IsGuest(webContents))
+            return;
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
         WebContentsDelegateQt* delegate = static_cast<WebContentsDelegateQt*>(webContents->GetDelegate());
         if (delegate)
             delegate->overrideWebPreferences(webContents, web_prefs);
@@ -404,6 +429,11 @@ void ContentBrowserClientQt::GetAdditionalWebUISchemes(std::vector<std::string>*
     additional_schemes->push_back(content::kChromeDevToolsScheme);
 }
 
+void ContentBrowserClientQt::GetAdditionalViewSourceSchemes(std::vector<std::string>* additional_schemes)
+{
+   additional_schemes->push_back(content::kChromeDevToolsScheme);
+}
+
 #if defined(Q_OS_LINUX)
 void ContentBrowserClientQt::GetAdditionalMappedFilesForChildProcess(const base::CommandLine& command_line, int child_process_id, content::PosixFileDescriptorInfo* mappings)
 {
@@ -736,4 +766,13 @@ bool ContentBrowserClientQt::ShouldIsolateErrorPage(bool in_main_frame)
     return false;
 }
 
+bool ContentBrowserClientQt::ShouldUseProcessPerSite(content::BrowserContext* browser_context, const GURL& effective_url)
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+     if (effective_url.SchemeIs(extensions::kExtensionScheme))
+        return true;
+#endif
+    return ContentBrowserClient::ShouldUseProcessPerSite(browser_context, effective_url);
+}
+
 } // namespace QtWebEngineCore
diff --git a/src/core/content_browser_client_qt.h b/src/core/content_browser_client_qt.h
index 471443a81..fc938f882 100644
--- a/src/core/content_browser_client_qt.h
+++ b/src/core/content_browser_client_qt.h
@@ -112,6 +112,8 @@ public:
     std::string GetApplicationLocale() override;
     std::string GetAcceptLangs(content::BrowserContext* context) override;
     void AppendExtraCommandLineSwitches(base::CommandLine* command_line, int child_process_id) override;
+
+    void GetAdditionalViewSourceSchemes(std::vector<std::string>* additional_schemes) override;
     void GetAdditionalWebUISchemes(std::vector<std::string>* additional_schemes) override;
 
     void BindInterfaceRequestFromFrame(content::RenderFrameHost* render_frame_host,
@@ -174,6 +176,7 @@ public:
     std::unique_ptr<device::LocationProvider> OverrideSystemLocationProvider() override;
 #endif
     bool ShouldIsolateErrorPage(bool in_main_frame) override;
+    bool ShouldUseProcessPerSite(content::BrowserContext* browser_context, const GURL& effective_url) override;
 
 #if defined(Q_OS_LINUX)
     void GetAdditionalMappedFilesForChildProcess(const base::CommandLine& command_line, int child_process_id, content::PosixFileDescriptorInfo* mappings) override;
diff --git a/src/core/content_client_qt.cpp b/src/core/content_client_qt.cpp
index 41e3f7f6c..9065174b8 100644
--- a/src/core/content_client_qt.cpp
+++ b/src/core/content_client_qt.cpp
@@ -84,6 +84,14 @@ const char kWidevineCdmFileName[] =
 #endif
 #endif
 
+#if QT_CONFIG(webengine_printing_and_pdf)
+#include "pdf/pdf.h"
+#include "pdf/pdf_ppapi.h"
+const char kPdfPluginMimeType[] = "application/x-google-chrome-pdf";
+const char kPdfPluginPath[] = "internal-pdf-viewer/";
+const char kPdfPluginSrc[] = "src";
+#endif // QT_CONFIG(webengine_printing_and_pdf)
+
 static QString webenginePluginsPath()
 {
     // Look for plugins in /plugins/webengine or application dir.
@@ -98,7 +106,6 @@ static QString webenginePluginsPath()
 }
 #endif  // BUILDFLAG(ENABLE_LIBRARY_CDMS)
 
-
 #if defined(Q_OS_WIN)
 #include <shlobj.h>
 static QString getLocalAppDataDir()
@@ -234,10 +241,30 @@ void AddPepperFlashFromCommandLine(std::vector<content::PepperPluginInfo>* plugi
     plugins->push_back(CreatePepperFlashInfo(base::FilePath(flash_path), flash_version));
 }
 
+void ComputeBuiltInPlugins(std::vector<content::PepperPluginInfo>* plugins)
+{
+#if QT_CONFIG(webengine_printing_and_pdf)
+    content::PepperPluginInfo pdf_info;
+    pdf_info.is_internal = true;
+    pdf_info.is_out_of_process = true;
+    pdf_info.name = "Chromium PDF Viewer";
+    pdf_info.description = "Portable Document Format";
+    pdf_info.path = base::FilePath::FromUTF8Unsafe(kPdfPluginPath);
+    content::WebPluginMimeType pdf_mime_type(kPdfPluginMimeType, "pdf", "Portable Document Format");
+    pdf_info.mime_types.push_back(pdf_mime_type);
+    pdf_info.internal_entry_points.get_interface = chrome_pdf::PPP_GetInterface;
+    pdf_info.internal_entry_points.initialize_module = chrome_pdf::PPP_InitializeModule;
+    pdf_info.internal_entry_points.shutdown_module = chrome_pdf::PPP_ShutdownModule;
+    pdf_info.permissions = ppapi::PERMISSION_PRIVATE | ppapi::PERMISSION_DEV | ppapi::PERMISSION_PDF;
+    plugins->push_back(pdf_info);
+#endif // QT_CONFIG(webengine_printing_and_pdf)
+}
+
 namespace QtWebEngineCore {
 
 void ContentClientQt::AddPepperPlugins(std::vector<content::PepperPluginInfo>* plugins)
 {
+    ComputeBuiltInPlugins(plugins);
     AddPepperFlashFromSystem(plugins);
     AddPepperFlashFromCommandLine(plugins);
 }
@@ -319,7 +346,6 @@ static bool IsWidevineAvailable(base::FilePath *cdm_path,
 }
 #endif  // defined(WIDEVINE_CDM_AVAILABLE_NOT_COMPONENT)
 
-
 void ContentClientQt::AddContentDecryptionModules(std::vector<content::CdmInfo> *cdms,
                                                   std::vector<media::CdmHostFilePath> *cdm_host_file_paths)
 {
@@ -375,6 +401,11 @@ void ContentClientQt::AddContentDecryptionModules(std::vector<content::CdmInfo>
     }
 }
 
+void ContentClientQt::AddAdditionalSchemes(Schemes* schemes)
+{
+    schemes->standard_schemes.push_back("chrome-extension");
+}
+
 std::string ContentClientQt::getUserAgent()
 {
     // Mention the Chromium version we're based on to get passed stupid UA-string-based feature detection (several WebRTC demos need this)
diff --git a/src/core/content_client_qt.h b/src/core/content_client_qt.h
index c3feded00..bee79986c 100644
--- a/src/core/content_client_qt.h
+++ b/src/core/content_client_qt.h
@@ -56,6 +56,7 @@ public:
 #endif
     void AddContentDecryptionModules(std::vector<content::CdmInfo> *cdms,
                                      std::vector<media::CdmHostFilePath> *cdm_host_file_paths) override;
+    void AddAdditionalSchemes(Schemes* schemes) override;
 
     base::StringPiece GetDataResource(int, ui::ScaleFactor) const override;
     base::RefCountedMemory* GetDataResourceBytes(int resource_id) const override;
diff --git a/src/core/core_chromium.pri b/src/core/core_chromium.pri
index 584439840..edf6806a3 100644
--- a/src/core/core_chromium.pri
+++ b/src/core/core_chromium.pri
@@ -310,3 +310,39 @@ qtConfig(webengine-webchannel) {
     SOURCES += renderer/web_channel_ipc_transport.cpp \
                renderer_host/web_channel_ipc_transport_host.cpp
 }
+
+qtConfig(webengine-extensions) {
+    SOURCES += \
+        common/extensions/extensions_api_provider_qt.cpp \
+        common/extensions/extensions_client_qt.cpp \
+        extensions/component_extension_resource_manager_qt.cpp \
+        extensions/extension_system_qt.cpp \
+        extensions/extension_system_factory_qt.cpp \
+        extensions/extension_web_contents_observer_qt.cpp \
+        extensions/extensions_api_client_qt.cpp \
+        extensions/extensions_browser_api_provider_qt.cpp \
+        extensions/extensions_browser_client_qt.cpp \
+        extensions/mime_handler_view_guest_delegate_qt.cpp \
+        renderer/extensions/extensions_dispatcher_delegate_qt.cpp \
+        renderer/extensions/extensions_renderer_client_qt.cpp \
+        renderer/extensions/renderer_permissions_policy_delegate_qt.cpp \
+        renderer/extensions/resource_request_policy_qt.cpp \
+        renderer_host/resource_dispatcher_host_delegate_qt.cpp
+
+    HEADERS += \
+        common/extensions/extensions_api_provider_qt.h \
+        common/extensions/extensions_client_qt.h \
+        extensions/component_extension_resource_manager_qt.h \
+        extensions/extension_system_qt.h \
+        extensions/extension_system_factory_qt.h \
+        extensions/extension_web_contents_observer_qt.h \
+        extensions/extensions_api_client_qt.h \
+        extensions/extensions_browser_api_provider_qt.h \
+        extensions/extensions_browser_client_qt.h \
+        extensions/mime_handler_view_guest_delegate_qt.h \
+        renderer/extensions/extensions_dispatcher_delegate_qt.h \
+        renderer/extensions/extensions_renderer_client_qt.h \
+        renderer/extensions/renderer_permissions_policy_delegate_qt.h \
+        renderer/extensions/resource_request_policy_qt.h \
+        renderer_host/resource_dispatcher_host_delegate_qt.h
+}
diff --git a/src/core/core_gn_config.pri b/src/core/core_gn_config.pri
index 9b0145dfc..b76cdc81a 100644
--- a/src/core/core_gn_config.pri
+++ b/src/core/core_gn_config.pri
@@ -1,11 +1,19 @@
+include($$QTWEBENGINE_OUT_ROOT/src/core/qtwebenginecore-config.pri)
+QT_FOR_CONFIG += webenginecore webenginecore-private
+
 CONFIG = gn_generator $$CONFIG
 GN_SRC_DIR = $$PWD
 GN_FILE = $$OUT_PWD/$$getConfigDir()/BUILD.gn
 GN_FIND_MOCABLES_SCRIPT = $$shell_path($$QTWEBENGINE_ROOT/tools/scripts/gn_find_mocables.py)
 GN_RUN_BINARY_SCRIPT = $$shell_path($$QTWEBENGINE_ROOT/tools/scripts/gn_run_binary.py)
 GN_IMPORTS =  $$PWD/qtwebengine.gni
-GN_INCLUDES = $$PWD/qtwebengine_sources.gni $$PWD/qtwebengine_resources.gni
+qtConfig (webengine-extensions) {
+  GN_INCLUDES += $$PWD/qtwebengine_sources.gni $$PWD/qtwebengine_resources.gni $$PWD/common/extensions/api/qtwebengine_extensions_features.gni
+} else {
+  GN_INCLUDES = $$PWD/qtwebengine_sources.gni $$PWD/qtwebengine_resources.gni
+}
 GN_CORE_INCLUDE_DIRS = $$PWD/service
 GN_CREATE_PRI = true
 QMAKE_INTERNAL_INCLUDED_FILES = $$GN_IMPORTS $$GN_INCLUDES $$GN_FILE
 
+
diff --git a/src/core/extensions/component_extension_resource_manager_qt.cpp b/src/core/extensions/component_extension_resource_manager_qt.cpp
new file mode 100644
index 000000000..d8326400e
--- /dev/null
+++ b/src/core/extensions/component_extension_resource_manager_qt.cpp
@@ -0,0 +1,94 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// based on chrome/browser/extensions/chrome_component_extension_resource_manager.cc:
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "component_extension_resource_manager_qt.h"
+
+#include "base/logging.h"
+#include "base/path_service.h"
+#include "chrome/grit/component_extension_resources_map.h"
+
+namespace extensions {
+
+ComponentExtensionResourceManagerQt::ComponentExtensionResourceManagerQt()
+{
+    AddComponentResourceEntries(kComponentExtensionResources,
+                                kComponentExtensionResourcesSize);
+}
+
+ComponentExtensionResourceManagerQt::~ComponentExtensionResourceManagerQt() {}
+
+bool ComponentExtensionResourceManagerQt::IsComponentExtensionResource(const base::FilePath &extension_path,
+                                                                       const base::FilePath &resource_path,
+                                                                       int *resource_id) const
+{
+    base::FilePath directory_path = extension_path;
+    base::FilePath resources_dir;
+    base::FilePath relative_path;
+    if (!base::PathService::Get(base::DIR_QT_LIBRARY_DATA, &resources_dir)
+            || !resources_dir.AppendRelativePath(directory_path, &relative_path)) {
+        return false;
+    }
+
+    relative_path = relative_path.Append(resource_path);
+    relative_path = relative_path.NormalizePathSeparators();
+
+    std::map<base::FilePath, int>::const_iterator entry = path_to_resource_id_.find(relative_path);
+    if (entry != path_to_resource_id_.end())
+        *resource_id = entry->second;
+
+    return entry != path_to_resource_id_.end();
+}
+
+void ComponentExtensionResourceManagerQt::AddComponentResourceEntries(const GritResourceMap *entries, size_t size)
+{
+    for (size_t i = 0; i < size; ++i) {
+        base::FilePath resource_path = base::FilePath().AppendASCII(entries[i].name);
+        resource_path = resource_path.NormalizePathSeparators();
+
+        DCHECK(path_to_resource_id_.find(resource_path) == path_to_resource_id_.end());
+        path_to_resource_id_[resource_path] = entries[i].value;
+    }
+}
+
+} // namespace extensions
diff --git a/src/core/extensions/component_extension_resource_manager_qt.h b/src/core/extensions/component_extension_resource_manager_qt.h
new file mode 100644
index 000000000..f12edf61e
--- /dev/null
+++ b/src/core/extensions/component_extension_resource_manager_qt.h
@@ -0,0 +1,79 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef COMPONENT_EXTENSION_RESOURCE_MANAGER_QT_H_
+#define COMPONENT_EXTENSION_RESOURCE_MANAGER_QT_H_
+
+#include <map>
+
+#include "base/files/file_path.h"
+#include "extensions/browser/component_extension_resource_manager.h"
+
+struct GritResourceMap;
+
+namespace extensions {
+
+class ComponentExtensionResourceManagerQt : public ComponentExtensionResourceManager
+{
+public:
+    ComponentExtensionResourceManagerQt();
+    ~ComponentExtensionResourceManagerQt() override;
+
+    // Overridden from ComponentExtensionResourceManager:
+    bool IsComponentExtensionResource(const base::FilePath &extension_path,
+                                      const base::FilePath &resource_path,
+                                      int *resource_id) const override;
+
+private:
+    void AddComponentResourceEntries(const GritResourceMap* entries, size_t size);
+
+    // A map from a resource path to the resource ID.  Used by
+    // IsComponentExtensionResource.
+    std::map<base::FilePath, int> path_to_resource_id_;
+
+    DISALLOW_COPY_AND_ASSIGN(ComponentExtensionResourceManagerQt);
+};
+
+} // namespace extensions
+
+#endif // COMPONENT_EXTENSION_RESOURCE_MANAGER_QT_H_
diff --git a/src/core/extensions/extension_system_factory_qt.cpp b/src/core/extensions/extension_system_factory_qt.cpp
new file mode 100644
index 000000000..41ba31214
--- /dev/null
+++ b/src/core/extensions/extension_system_factory_qt.cpp
@@ -0,0 +1,98 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extension_system_factory_qt.h"
+
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+#include "extensions/browser/declarative_user_script_manager_factory.h"
+#include "extensions/browser/event_router_factory.h"
+#include "extensions/browser/extension_prefs_factory.h"
+#include "extensions/browser/extension_registry_factory.h"
+#include "extensions/browser/extension_system.h"
+#include "extensions/browser/extensions_browser_client.h"
+#include "extensions/browser/process_manager_factory.h"
+#include "extensions/browser/renderer_startup_helper.h"
+
+namespace extensions {
+
+// static
+ExtensionSystem *ExtensionSystemFactoryQt::GetForBrowserContext(content::BrowserContext *context)
+{
+    return static_cast<ExtensionSystem *>(GetInstance()->GetServiceForBrowserContext(context, true));
+}
+
+// static
+ExtensionSystemFactoryQt *ExtensionSystemFactoryQt::GetInstance()
+{
+    return base::Singleton<ExtensionSystemFactoryQt>::get();
+}
+
+ExtensionSystemFactoryQt::ExtensionSystemFactoryQt()
+        : ExtensionSystemProvider("ExtensionSystem", BrowserContextDependencyManager::GetInstance())
+{
+    DCHECK(ExtensionsBrowserClient::Get()) << "ExtensionSystemFactory must be initialized after BrowserProcess";
+    DependsOn(ExtensionPrefsFactory::GetInstance());
+    DependsOn(ExtensionRegistryFactory::GetInstance());
+}
+
+ExtensionSystemFactoryQt::~ExtensionSystemFactoryQt()
+{
+}
+
+KeyedService *ExtensionSystemFactoryQt::BuildServiceInstanceFor(content::BrowserContext *context) const
+{
+    return new ExtensionSystemQt(context);
+}
+
+content::BrowserContext *ExtensionSystemFactoryQt::GetBrowserContextToUse(content::BrowserContext *context) const
+{
+    // Separate instance in incognito.
+    return context;
+}
+
+bool ExtensionSystemFactoryQt::ServiceIsCreatedWithBrowserContext() const
+{
+    return true;
+}
+
+} // namespace extensions
diff --git a/src/core/extensions/extension_system_factory_qt.h b/src/core/extensions/extension_system_factory_qt.h
new file mode 100644
index 000000000..6e840b6d6
--- /dev/null
+++ b/src/core/extensions/extension_system_factory_qt.h
@@ -0,0 +1,82 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXTENSION_SYSTEM_FACTORY_QT_H_
+#define EXTENSION_SYSTEM_FACTORY_QT_H_
+
+#include "base/macros.h"
+#include "base/memory/singleton.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+#include "extensions/browser/extension_system_provider.h"
+#include "extension_system_qt.h"
+
+namespace extensions {
+class ExtensionSystem;
+
+// BrowserContextKeyedServiceFactory for ExtensionSystemImpl.
+// TODO(yoz): Rename to ExtensionSystemImplFactory.
+class ExtensionSystemFactoryQt : public ExtensionSystemProvider
+{
+public:
+    // ExtensionSystem provider implementation:
+    ExtensionSystem *GetForBrowserContext(content::BrowserContext *context) override;
+
+    static ExtensionSystemFactoryQt *GetInstance();
+
+private:
+    friend struct base::DefaultSingletonTraits<ExtensionSystemFactoryQt>;
+
+    ExtensionSystemFactoryQt();
+    ~ExtensionSystemFactoryQt() override;
+
+    // BrowserContextKeyedServiceFactory implementation:
+    KeyedService *BuildServiceInstanceFor(content::BrowserContext *context) const override;
+    content::BrowserContext *GetBrowserContextToUse(content::BrowserContext *context) const override;
+    bool ServiceIsCreatedWithBrowserContext() const override;
+
+    DISALLOW_COPY_AND_ASSIGN(ExtensionSystemFactoryQt);
+};
+
+} // namespace extensions
+
+#endif // EXTENSION_SYSTEM_FACTORY_QT_H_
diff --git a/src/core/extensions/extension_system_qt.cpp b/src/core/extensions/extension_system_qt.cpp
new file mode 100644
index 000000000..4ca407421
--- /dev/null
+++ b/src/core/extensions/extension_system_qt.cpp
@@ -0,0 +1,447 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extension_system_qt.h"
+
+#include <algorithm>
+
+#include "base/base_paths.h"
+#include "base/base_switches.h"
+#include "base/bind.h"
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/files/file_util.h"
+#include "base/json/json_string_value_serializer.h"
+#include "base/memory/ptr_util.h"
+#include "base/memory/weak_ptr.h"
+#include "base/path_service.h"
+#include "base/strings/string_tokenizer.h"
+#include "base/strings/utf_string_conversions.h"
+#include "base/task/post_task.h"
+#include "base/time/time.h"
+#include "base/trace_event/trace_event.h"
+#include "build/build_config.h"
+#include "components/crx_file/id_util.h"
+#include "content/public/browser/browser_context.h"
+#include "content/public/browser/browser_task_traits.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/plugin_service.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/url_data_source.h"
+#include "content/public/common/webplugininfo.h"
+#include "extensions/browser/content_verifier.h"
+#include "extensions/browser/content_verifier_delegate.h"
+#include "extensions/browser/extension_pref_store.h"
+#include "extensions/browser/extension_pref_value_map.h"
+#include "extensions/browser/extension_pref_value_map_factory.h"
+#include "extensions/browser/extension_prefs.h"
+#include "extensions/browser/extension_registry.h"
+#include "extensions/browser/info_map.h"
+#include "extensions/browser/notification_types.h"
+#include "extensions/browser/null_app_sorting.h"
+#include "extensions/browser/quota_service.h"
+#include "extensions/browser/renderer_startup_helper.h"
+#include "extensions/browser/runtime_data.h"
+#include "extensions/browser/shared_user_script_master.h"
+#include "extensions/browser/service_worker_manager.h"
+#include "extensions/browser/value_store/value_store_factory_impl.h"
+#include "extensions/common/constants.h"
+#include "extensions/common/extension_messages.h"
+#include "extensions/common/manifest_constants.h"
+#include "extensions/common/manifest_handlers/mime_types_handler.h"
+#include "extensions/common/manifest_url_handlers.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "chrome/grit/component_extension_resources.h"
+#include "chrome/grit/browser_resources.h"
+#include "net/base/mime_util.h"
+
+using content::BrowserThread;
+
+namespace extensions {
+
+namespace {
+
+std::string GenerateId(const base::DictionaryValue *manifest,
+                       const base::FilePath &path)
+{
+    std::string raw_key;
+    std::string id_input;
+    CHECK(manifest->GetString(manifest_keys::kPublicKey, &raw_key));
+    CHECK(Extension::ParsePEMKeyBytes(raw_key, &id_input));
+    std::string id = crx_file::id_util::GenerateId(id_input);
+    return id;
+}
+
+// Implementation based on ComponentLoader::ParseManifest.
+std::unique_ptr<base::DictionaryValue> ParseManifest(const std::string &manifest_contents)
+{
+    JSONStringValueDeserializer deserializer(manifest_contents);
+    std::unique_ptr<base::Value> manifest(deserializer.Deserialize(NULL, NULL));
+
+    if (!manifest.get() || !manifest->is_dict()) {
+        LOG(ERROR) << "Failed to parse extension manifest.";
+        return NULL;
+    }
+    // Transfer ownership to the caller.
+    return base::DictionaryValue::From(std::move(manifest));
+}
+
+} // namespace
+
+// Dummy Content Verifier Delegate. Added to prevent crashes.
+class ContentVerifierDelegateQt
+        : public ContentVerifierDelegate {
+ public:
+  ~ContentVerifierDelegateQt() override {}
+
+  // This should return what verification mode is appropriate for the given
+  // extension, if any.
+    Mode ShouldBeVerified(const Extension& extension) override {
+        return NONE;
+    }
+
+  // Should return the public key to use for validating signatures via the two
+  // out parameters.
+    ContentVerifierKey GetPublicKey() override {
+        return ContentVerifierKey();
+    }
+  // This should return a URL that can be used to fetch the
+  // verified_contents.json containing signatures for the given extension
+  // id/version pair.
+  GURL GetSignatureFetchUrl(const std::string& extension_id,
+                            const base::Version& version) override {
+      return GURL();
+  }
+
+  // This should return the set of file paths for images used within the
+  // browser process. (These may get transcoded during the install process).
+  std::set<base::FilePath> GetBrowserImagePaths(
+          const extensions::Extension* extension) override {
+      return std::set<base::FilePath>();
+  }
+
+  // Called when the content verifier detects that a read of a file inside
+  // an extension did not match its expected hash.
+  void VerifyFailed(const std::string& extension_id,
+                            ContentVerifyJob::FailureReason reason) override {
+
+  }
+
+  // Called when ExtensionSystem is shutting down.
+  void Shutdown() override {
+
+  }
+};
+
+void ExtensionSystemQt::LoadExtension(std::string extension_id, std::unique_ptr<base::DictionaryValue> manifest, const base::FilePath &directory)
+{
+    int flags = Extension::REQUIRE_KEY;
+    std::string error;
+    scoped_refptr<const Extension> extension = Extension::Create(
+            directory,
+            Manifest::COMPONENT,
+            *manifest,
+            flags,
+            &error);
+    if (!extension.get())
+        LOG(ERROR) << error;
+
+    base::PostTaskWithTraits(FROM_HERE, {content::BrowserThread::IO},
+            base::Bind(&InfoMap::AddExtension,
+                       base::Unretained(info_map()),
+                       base::RetainedRef(extension),
+                       base::Time::Now(),
+                       true,
+                       false));
+    extension_registry_->AddEnabled(extension.get());
+
+    NotifyExtensionLoaded(extension.get());
+}
+
+void ExtensionSystemQt::OnExtensionRegisteredWithRequestContexts(scoped_refptr<const extensions::Extension> extension)
+{
+    extension_registry_->AddReady(extension);
+    if (extension_registry_->enabled_extensions().Contains(extension->id()))
+        extension_registry_->TriggerOnReady(extension.get());
+}
+
+// Implementation based on ExtensionService::NotifyExtensionLoaded.
+void ExtensionSystemQt::NotifyExtensionLoaded(const Extension *extension)
+{
+    // The URLRequestContexts need to be first to know that the extension
+    // was loaded, otherwise a race can arise where a renderer that is created
+    // for the extension may try to load an extension URL with an extension id
+    // that the request context doesn't yet know about. The profile is responsible
+    // for ensuring its URLRequestContexts appropriately discover the loaded
+    // extension.
+    RegisterExtensionWithRequestContexts(
+            extension,
+            base::Bind(&ExtensionSystemQt::OnExtensionRegisteredWithRequestContexts,
+                       weak_ptr_factory_.GetWeakPtr(),
+                       base::WrapRefCounted(extension)));
+
+    // Tell renderers about the loaded extension.
+    renderer_helper_->OnExtensionLoaded(*extension);
+
+    // Tell subsystems that use the ExtensionRegistryObserver::OnExtensionLoaded
+    // about the new extension.
+    //
+    // NOTE: It is important that this happen after notifying the renderers about
+    // the new extensions so that if we navigate to an extension URL in
+    // ExtensionRegistryObserver::OnExtensionLoaded the renderer is guaranteed to
+    // know about it.
+    extension_registry_->TriggerOnLoaded(extension);
+
+    // Register plugins included with the extension.
+    // Implementation based on PluginManager::OnExtensionLoaded.
+    const MimeTypesHandler *handler = MimeTypesHandler::GetHandler(extension);
+    if (handler && !handler->handler_url().empty()) {
+        content::WebPluginInfo info;
+        info.type = content::WebPluginInfo::PLUGIN_TYPE_BROWSER_PLUGIN;
+        info.name = base::UTF8ToUTF16(extension->name());
+        info.path = base::FilePath::FromUTF8Unsafe(extension->url().spec());
+        for (std::set<std::string>::const_iterator mime_type = handler->mime_type_set().begin();
+             mime_type != handler->mime_type_set().end(); ++mime_type) {
+            content::WebPluginMimeType mime_type_info;
+            mime_type_info.mime_type = *mime_type;
+            base::FilePath::StringType file_extension;
+            if (net::GetPreferredExtensionForMimeType(*mime_type, &file_extension)) {
+                mime_type_info.file_extensions.push_back(
+                        base::FilePath(file_extension).AsUTF8Unsafe());
+            }
+            info.mime_types.push_back(mime_type_info);
+        }
+        content::PluginService *plugin_service =
+                content::PluginService::GetInstance();
+        plugin_service->RefreshPlugins();
+        plugin_service->RegisterInternalPlugin(info, true);
+    }
+}
+
+bool ExtensionSystemQt::FinishDelayedInstallationIfReady(const std::string &extension_id, bool install_immediately)
+{
+    // TODO mibrunin
+    return false;
+}
+
+void ExtensionSystemQt::Shutdown()
+{
+    if (content_verifier_.get())
+        content_verifier_->Shutdown();
+}
+
+ServiceWorkerManager *ExtensionSystemQt::service_worker_manager()
+{
+    return service_worker_manager_.get();
+}
+
+ExtensionService *ExtensionSystemQt::extension_service()
+{
+    return nullptr;
+}
+
+RuntimeData *ExtensionSystemQt::runtime_data()
+{
+    return runtime_data_.get();
+}
+
+ManagementPolicy *ExtensionSystemQt::management_policy()
+{
+    return nullptr;
+}
+
+SharedUserScriptMaster *ExtensionSystemQt::shared_user_script_master()
+{
+    return shared_user_script_master_.get();
+}
+
+StateStore *ExtensionSystemQt::state_store()
+{
+    return nullptr;
+}
+
+StateStore *ExtensionSystemQt::rules_store()
+{
+    return nullptr;
+}
+
+scoped_refptr<ValueStoreFactory> ExtensionSystemQt::store_factory()
+{
+    return store_factory_;
+}
+
+InfoMap *ExtensionSystemQt::info_map()
+{
+    if (!info_map_.get())
+        info_map_ = new InfoMap;
+    return info_map_.get();
+}
+
+QuotaService *ExtensionSystemQt::quota_service()
+{
+    return quota_service_.get();
+}
+
+AppSorting *ExtensionSystemQt::app_sorting()
+{
+    return app_sorting_.get();
+}
+
+ContentVerifier *ExtensionSystemQt::content_verifier()
+{
+    if (!content_verifier_.get()) {
+        content_verifier_ = new ContentVerifier(browser_context_, std::make_unique<ContentVerifierDelegateQt>());
+    }
+    return content_verifier_.get();
+}
+
+ExtensionSystemQt::ExtensionSystemQt(content::BrowserContext *browserContext)
+    : browser_context_(browserContext)
+    , store_factory_(new ValueStoreFactoryImpl(browserContext->GetPath()))
+    , extension_registry_(ExtensionRegistry::Get(browserContext))
+    , renderer_helper_(extensions::RendererStartupHelperFactory::GetForBrowserContext(browserContext))
+    , initialized_(false)
+    , weak_ptr_factory_(this)
+{
+}
+
+ExtensionSystemQt::~ExtensionSystemQt()
+{
+}
+
+void ExtensionSystemQt::Init(bool extensions_enabled)
+{
+    if (initialized_)
+        return;
+
+    initialized_ = true;
+
+    service_worker_manager_.reset(new ServiceWorkerManager(browser_context_));
+    runtime_data_.reset(new RuntimeData(extension_registry_));
+    quota_service_.reset(new QuotaService);
+    app_sorting_.reset(new NullAppSorting);
+
+    shared_user_script_master_ =
+        std::make_unique<SharedUserScriptMaster>(browser_context_);
+
+    // Make the chrome://extension-icon/ resource available.
+    // content::URLDataSource::Add(browser_context_, new ExtensionIconSource(browser_context_));
+
+    if (extensions_enabled) {
+        // Inform the rest of the extensions system to start.
+        ready_.Signal();
+        content::NotificationService::current()->Notify(
+            NOTIFICATION_EXTENSIONS_READY_DEPRECATED,
+            content::Source<content::BrowserContext>(browser_context_),
+            content::NotificationService::NoDetails());
+
+        std::string pdf_manifest = ui::ResourceBundle::GetSharedInstance().GetRawDataResource(IDR_PDF_MANIFEST).as_string();
+        base::ReplaceFirstSubstringAfterOffset(&pdf_manifest, 0, "<NAME>", "chromium-pdf");
+
+        std::unique_ptr<base::DictionaryValue> pdfManifestDict = ParseManifest(pdf_manifest);
+        base::FilePath path;
+        base::PathService::Get(base::DIR_QT_LIBRARY_DATA, &path);
+        path = path.Append(base::FilePath(FILE_PATH_LITERAL("pdf")));
+        std::string id = GenerateId(pdfManifestDict.get(), path);
+        LoadExtension(id, std::move(pdfManifestDict), path);
+    }
+}
+
+void ExtensionSystemQt::InitForRegularProfile(bool extensions_enabled)
+{
+    if (initialized_)
+        return; // Already initialized.
+    // The InfoMap needs to be created before the ProcessManager.
+    info_map();
+
+    Init(extensions_enabled);
+}
+
+void ExtensionSystemQt::InitForIncognitoProfile()
+{
+    NOTIMPLEMENTED();
+}
+
+std::unique_ptr<ExtensionSet> ExtensionSystemQt::GetDependentExtensions(const Extension *extension)
+{
+    return base::WrapUnique(new ExtensionSet());
+}
+
+#if !defined(TOOLKIT_QT)
+void ExtensionSystemQt::InstallUpdate(const std::string &extension_id,
+                                      const std::string &public_key,
+                                      const base::FilePath &unpacked_dir,
+                                      bool install_immediately,
+                                      InstallUpdateCallback install_update_callback)
+{
+    NOTREACHED() << "Not yet implemented";
+    base::DeleteFile(unpacked_dir, true /* recursive */);
+    std::move(install_update_callback).Run(CrxInstallError(CrxInstallErrorType::DECLINED, CrxInstallErrorDetail::DISALLOWED_BY_POLICY));
+}
+#endif
+
+void ExtensionSystemQt::RegisterExtensionWithRequestContexts(const Extension *extension,
+                                                             const base::Closure &callback)
+{
+    base::Time install_time = base::Time::Now();
+
+    bool incognito_enabled = false;
+    bool notifications_disabled = false;
+
+    base::PostTaskWithTraitsAndReply(
+            FROM_HERE, {BrowserThread::IO},
+            base::Bind(&InfoMap::AddExtension, info_map(),
+                       base::RetainedRef(extension), install_time, incognito_enabled,
+                       notifications_disabled),
+            callback);
+}
+
+void ExtensionSystemQt::UnregisterExtensionWithRequestContexts(const std::string &extension_id,
+                                                               const UnloadedExtensionReason reason)
+{
+    base::PostTaskWithTraits(
+        FROM_HERE, {BrowserThread::IO},
+        base::Bind(&InfoMap::RemoveExtension, info_map(), extension_id, reason));
+}
+} // namespace extensions
diff --git a/src/core/extensions/extension_system_qt.h b/src/core/extensions/extension_system_qt.h
new file mode 100644
index 000000000..0ebe1d044
--- /dev/null
+++ b/src/core/extensions/extension_system_qt.h
@@ -0,0 +1,158 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Large parts of this file are based on the source code from the file
+// chrome/browser/extensions/extension_system_impl.h from the Chromium sources.
+
+#ifndef EXTENSION_SYSTEM_QT_H
+#define EXTENSION_SYSTEM_QT_H
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "build/build_config.h"
+#include "extensions/browser/extension_system.h"
+#include "extensions/common/extension_set.h"
+#include "extensions/common/one_shot_event.h"
+
+namespace extensions {
+
+class ExtensionRegistry;
+class InfoMap;
+class RendererStartupHelper;
+class ServiceWorkerManager;
+class StateStoreNotificationObserver;
+class ValueStoreFactory;
+class ValueStoreFactoryImpl;
+
+// The ExtensionSystem for ProfileImpl and OffTheRecordProfileImpl.
+// Implementation details: non-shared services are owned by
+// ExtensionSystemImpl, a KeyedService with separate incognito
+// instances. A private Shared class (also a KeyedService,
+// but with a shared instance for incognito) keeps the common services.
+class ExtensionSystemQt : public ExtensionSystem
+{
+public:
+    explicit ExtensionSystemQt(content::BrowserContext *browserContext);
+    ~ExtensionSystemQt() override;
+
+    // Initializes the extension system.
+    void Initialize();
+
+    // KeyedService implementation:
+    void Shutdown() override;
+
+    // ExtensionSystem implementation:
+    void InitForRegularProfile(bool extensions_enabled) override;
+    void InitForIncognitoProfile() override;
+    ExtensionService *extension_service() override;
+    RuntimeData *runtime_data() override;
+    ManagementPolicy *management_policy() override;
+    ServiceWorkerManager *service_worker_manager() override;
+    SharedUserScriptMaster *shared_user_script_master() override;
+    StateStore* state_store() override;
+    StateStore* rules_store() override;
+    scoped_refptr<ValueStoreFactory> store_factory() override;
+    InfoMap *info_map() override;
+    QuotaService *quota_service() override;
+    AppSorting *app_sorting() override;
+
+    void RegisterExtensionWithRequestContexts(const Extension *extension,
+                                              const base::Closure &callback) override;
+
+    void UnregisterExtensionWithRequestContexts(const std::string &extension_id,
+                                                const UnloadedExtensionReason reason) override;
+
+    ContentVerifier *content_verifier() override;
+    std::unique_ptr<ExtensionSet> GetDependentExtensions(const Extension *extension) override;
+
+#if !defined(TOOLKIT_QT)
+    void InstallUpdate(const std::string &extension_id,
+                       const std::string &public_key,
+                       const base::FilePath &unpacked_dir,
+                       bool install_immediately,
+                       InstallUpdateCallback install_update_callback) override;
+#endif // TOOLKIT_QT
+    //friend class ExtensionSystemSharedFactory;
+
+    bool FinishDelayedInstallationIfReady(const std::string &extension_id, bool install_immediately) override;
+
+    void Init(bool extensions_enabled);
+
+    const OneShotEvent &ready() const override { return ready_; }
+
+private:
+    void OnExtensionRegisteredWithRequestContexts(scoped_refptr<const extensions::Extension> extension);
+
+    void NotifyExtensionLoaded(const Extension *extension);
+    void LoadExtension(std::string extension_id, std::unique_ptr<base::DictionaryValue> manifest, const base::FilePath &directory);
+    // The services that are shared between normal and incognito profiles.
+
+    // Data to be accessed on the IO thread. Must outlive process_manager_.
+    scoped_refptr<InfoMap> info_map_;
+
+    std::unique_ptr<ServiceWorkerManager> service_worker_manager_;
+    std::unique_ptr<RuntimeData> runtime_data_;
+    std::unique_ptr<QuotaService> quota_service_;
+    std::unique_ptr<AppSorting> app_sorting_;
+    std::unique_ptr<SharedUserScriptMaster> shared_user_script_master_;
+
+
+    // For verifying the contents of extensions read from disk.
+    scoped_refptr<ContentVerifier> content_verifier_;
+    OneShotEvent ready_;
+
+    content::BrowserContext *browser_context_;
+    scoped_refptr<ValueStoreFactory> store_factory_;
+    ExtensionRegistry *extension_registry_;
+    extensions::RendererStartupHelper *renderer_helper_;
+    bool initialized_;
+
+    base::WeakPtrFactory<ExtensionSystemQt> weak_ptr_factory_;
+    DISALLOW_COPY_AND_ASSIGN(ExtensionSystemQt);
+};
+
+} // namespace extensions
+
+#endif // EXTENSION_SYSTEM_QT_H
diff --git a/src/core/extensions/extension_web_contents_observer_qt.cpp b/src/core/extensions/extension_web_contents_observer_qt.cpp
new file mode 100644
index 000000000..1eb2298ca
--- /dev/null
+++ b/src/core/extensions/extension_web_contents_observer_qt.cpp
@@ -0,0 +1,124 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extension_web_contents_observer_qt.h"
+
+#include "content/public/browser/child_process_security_policy.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/common/url_constants.h"
+#include "extensions/browser/extension_registry.h"
+#include "extensions/common/manifest.h"
+
+namespace extensions {
+
+ExtensionWebContentsObserverQt::ExtensionWebContentsObserverQt(content::WebContents *web_contents)
+    : ExtensionWebContentsObserver(web_contents)
+{
+}
+
+ExtensionWebContentsObserverQt::~ExtensionWebContentsObserverQt()
+{
+}
+
+// static
+void ExtensionWebContentsObserverQt::CreateForWebContents(content::WebContents *web_contents)
+{
+    content::WebContentsUserData<ExtensionWebContentsObserverQt>::CreateForWebContents(web_contents);
+
+    // Initialize this instance if necessary.
+    FromWebContents(web_contents)->Initialize();
+}
+
+std::string ExtensionWebContentsObserverQt::GetExtensionIdFromFrame(content::RenderFrameHost *render_frame_host) const
+{
+    const GURL &site = render_frame_host->GetSiteInstance()->GetSiteURL();
+    if (!site.SchemeIs(kExtensionScheme))
+        return std::string();
+
+    return site.host();
+}
+
+const Extension *ExtensionWebContentsObserverQt::GetExtensionFromFrame(content::RenderFrameHost *render_frame_host, bool verify_url) const
+{
+    std::string extension_id = GetExtensionIdFromFrame(render_frame_host);
+    if (extension_id.empty())
+        return nullptr;
+
+    content::BrowserContext *browser_context =
+            render_frame_host->GetProcess()->GetBrowserContext();
+    const Extension *extension = ExtensionRegistry::Get(browser_context)
+                                         ->enabled_extensions()
+                                         .GetByID(extension_id);
+    if (!extension)
+        return nullptr;
+
+    if (verify_url) {
+        const url::Origin &origin(render_frame_host->GetLastCommittedOrigin());
+        // Without site isolation, this check is needed to eliminate non-extension
+        // schemes. With site isolation, this is still needed to exclude sandboxed
+        // extension frames with a unique origin.
+        const GURL site_url(render_frame_host->GetSiteInstance()->GetSiteURL());
+        if (origin.opaque() || site_url != content::SiteInstance::GetSiteForURL(browser_context, origin.GetURL()))
+            return nullptr;
+    }
+
+    return extension;
+}
+
+void ExtensionWebContentsObserverQt::RenderFrameCreated(content::RenderFrameHost *render_frame_host)
+{
+    ExtensionWebContentsObserver::RenderFrameCreated(render_frame_host);
+
+    const Extension *extension = GetExtensionFromFrame(render_frame_host, false);
+    if (!extension)
+        return;
+
+    int process_id = render_frame_host->GetProcess()->GetID();
+    auto *policy = content::ChildProcessSecurityPolicy::GetInstance();
+
+    if (extension->is_extension() && Manifest::IsComponentLocation(extension->location()))
+        policy->GrantRequestOrigin(process_id, url::Origin::Create(GURL(content::kChromeUIResourcesURL)));
+}
+
+} // namespace extensions
diff --git a/src/core/extensions/extension_web_contents_observer_qt.h b/src/core/extensions/extension_web_contents_observer_qt.h
new file mode 100644
index 000000000..043b9d4fa
--- /dev/null
+++ b/src/core/extensions/extension_web_contents_observer_qt.h
@@ -0,0 +1,75 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXTENSION_WEB_CONTENTS_OBSERVER_QT_H_
+#define EXTENSION_WEB_CONTENTS_OBSERVER_QT_H_
+
+#include "content/public/browser/web_contents_user_data.h"
+#include "extensions/browser/extension_web_contents_observer.h"
+
+namespace extensions {
+
+class ExtensionWebContentsObserverQt
+    : public ExtensionWebContentsObserver,
+      public content::WebContentsUserData<ExtensionWebContentsObserverQt>
+{
+public:
+    explicit ExtensionWebContentsObserverQt(content::WebContents *web_contents);
+    ~ExtensionWebContentsObserverQt() override;
+
+    static void CreateForWebContents(content::WebContents *web_contents);
+
+    std::string GetExtensionIdFromFrame(content::RenderFrameHost *) const;
+    const Extension *GetExtensionFromFrame(content::RenderFrameHost *, bool) const;
+
+    // content::WebContentsObserver overrides.
+    void RenderFrameCreated(content::RenderFrameHost *render_frame_host) override;
+
+private:
+    friend class content::WebContentsUserData<ExtensionWebContentsObserverQt>;
+    DISALLOW_COPY_AND_ASSIGN(ExtensionWebContentsObserverQt);
+};
+
+} // namespace extensions
+
+#endif // EXTENSION_WEB_CONTENTS_OBSERVER_QT_H_
diff --git a/src/core/extensions/extensions_api_client_qt.cpp b/src/core/extensions/extensions_api_client_qt.cpp
new file mode 100644
index 000000000..731b79a63
--- /dev/null
+++ b/src/core/extensions/extensions_api_client_qt.cpp
@@ -0,0 +1,85 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2015 The Chromium Embedded Framework Authors.
+// Portions copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions_api_client_qt.h"
+
+#include <memory>
+//#include "base/memory/ptr_util.h"
+#include "extension_web_contents_observer_qt.h"
+#include "components/pdf/browser/pdf_web_contents_helper.h"
+#include "extensions/browser/guest_view/extensions_guest_view_manager_delegate.h"
+#include "extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest_delegate.h"
+#include "printing/print_view_manager_qt.h"
+
+namespace extensions {
+
+ExtensionsAPIClientQt::ExtensionsAPIClientQt()
+{
+}
+
+AppViewGuestDelegate *ExtensionsAPIClientQt::CreateAppViewGuestDelegate() const
+{
+    // TODO(extensions): Implement to support Apps.
+    NOTREACHED();
+    return nullptr;
+}
+
+std::unique_ptr<guest_view::GuestViewManagerDelegate> ExtensionsAPIClientQt::CreateGuestViewManagerDelegate(content::BrowserContext *context) const
+{
+    return std::make_unique<guest_view::GuestViewManagerDelegate>();
+}
+
+std::unique_ptr<MimeHandlerViewGuestDelegate> ExtensionsAPIClientQt::CreateMimeHandlerViewGuestDelegate(MimeHandlerViewGuest *guest) const
+{
+    return std::make_unique<MimeHandlerViewGuestDelegate>();
+}
+
+void ExtensionsAPIClientQt::AttachWebContentsHelpers(content::WebContents *web_contents) const
+{
+    // PrefsTabHelper::CreateForWebContents(web_contents);
+    QtWebEngineCore::PrintViewManagerQt::CreateForWebContents(web_contents);
+    ExtensionWebContentsObserverQt::CreateForWebContents(web_contents);
+}
+
+} // namespace extensions
diff --git a/src/core/extensions/extensions_api_client_qt.h b/src/core/extensions/extensions_api_client_qt.h
new file mode 100644
index 000000000..2fa69f539
--- /dev/null
+++ b/src/core/extensions/extensions_api_client_qt.h
@@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2015 The Chromium Embedded Framework Authors.
+// Portions copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXTENSIONS_API_CLIENT_QT_H_
+#define EXTENSIONS_API_CLIENT_QT_H_
+
+#include "extensions/browser/api/extensions_api_client.h"
+
+namespace extensions {
+
+class ExtensionsAPIClientQt : public ExtensionsAPIClient
+{
+public:
+    ExtensionsAPIClientQt();
+
+    // ExtensionsAPIClient implementation.
+    AppViewGuestDelegate *CreateAppViewGuestDelegate() const override;
+    std::unique_ptr<guest_view::GuestViewManagerDelegate>
+    CreateGuestViewManagerDelegate(content::BrowserContext *context) const override;
+    std::unique_ptr<MimeHandlerViewGuestDelegate>
+    CreateMimeHandlerViewGuestDelegate(MimeHandlerViewGuest *guest) const override;
+    void AttachWebContentsHelpers(content::WebContents *web_contents) const override;
+};
+
+} // namespace extensions
+
+#endif // EXTENSIONS_API_CLIENT_QT_H_
diff --git a/src/core/extensions/extensions_browser_api_provider_qt.cpp b/src/core/extensions/extensions_browser_api_provider_qt.cpp
new file mode 100644
index 000000000..cc1932c64
--- /dev/null
+++ b/src/core/extensions/extensions_browser_api_provider_qt.cpp
@@ -0,0 +1,57 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "extensions_browser_api_provider_qt.h"
+
+#include "extensions/browser/api/generated_api_registration.h"
+
+namespace extensions {
+ExtensionsBrowserAPIProviderQt::ExtensionsBrowserAPIProviderQt() =
+    default;
+ExtensionsBrowserAPIProviderQt::~ExtensionsBrowserAPIProviderQt() =
+    default;
+
+void ExtensionsBrowserAPIProviderQt::RegisterExtensionFunctions(
+    ExtensionFunctionRegistry* registry) {
+    api::GeneratedFunctionRegistry::RegisterAll(registry);
+}
+
+
+}
+
diff --git a/src/core/extensions/extensions_browser_api_provider_qt.h b/src/core/extensions/extensions_browser_api_provider_qt.h
new file mode 100644
index 000000000..612df3825
--- /dev/null
+++ b/src/core/extensions/extensions_browser_api_provider_qt.h
@@ -0,0 +1,61 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef EXTENSIONS_API_PROVIDER_QT_H
+#define EXTENSIONS_API_PROVIDER_QT_H
+
+#include "extensions/browser/extensions_browser_api_provider.h"
+#include "base/macros.h"
+
+namespace extensions {
+
+class ExtensionsBrowserAPIProviderQt : public ExtensionsBrowserAPIProvider {
+public:
+    ExtensionsBrowserAPIProviderQt();
+    ~ExtensionsBrowserAPIProviderQt() override;
+
+    void RegisterExtensionFunctions(ExtensionFunctionRegistry *registry) override;
+
+private:
+    DISALLOW_COPY_AND_ASSIGN(ExtensionsBrowserAPIProviderQt);
+};
+
+}
+
+#endif // EXTENSIONS_API_PROVIDER_QT_H
diff --git a/src/core/extensions/extensions_browser_client_qt.cpp b/src/core/extensions/extensions_browser_client_qt.cpp
new file mode 100644
index 000000000..8bba4128f
--- /dev/null
+++ b/src/core/extensions/extensions_browser_client_qt.cpp
@@ -0,0 +1,499 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2015 The Chromium Embedded Framework Authors.
+// Portions copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions_browser_client_qt.h"
+
+#include <utility>
+
+#include "base/files/file_path.h"
+#include "base/memory/weak_ptr.h"
+#include "base/path_service.h"
+#include "base/strings/stringprintf.h"
+#include "base/task/post_task.h"
+#include "base/memory/ref_counted_memory.h"
+#include "chrome/browser/profiles/profile.h"
+#include "content/public/browser/browser_context.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_frame_host.h"
+#include "extensions/browser/api/extensions_api_client.h"
+#include "extensions/browser/api/runtime/runtime_api_delegate.h"
+#include "extensions/browser/app_sorting.h"
+#include "extensions/browser/core_extensions_browser_api_provider.h"
+#include "extensions/browser/event_router.h"
+#include "extensions/browser/extension_host_delegate.h"
+#include "extensions/browser/extension_protocols.h"
+#include "extensions/browser/mojo/interface_registration.h"
+#include "extensions/browser/url_request_util.h"
+#include "extensions/common/file_util.h"
+#include "net/base/completion_once_callback.h"
+#include "net/base/mime_util.h"
+#include "net/url_request/url_request_simple_job.h"
+#include "ui/base/resource/resource_bundle.h"
+
+#include "component_extension_resource_manager_qt.h"
+#include "extension_system_factory_qt.h"
+#include "extension_web_contents_observer_qt.h"
+#include "extensions_api_client_qt.h"
+#include "extensions_browser_api_provider_qt.h"
+#include "extensions_browser_client_qt.h"
+#include "web_engine_library_info.h"
+
+using content::BrowserContext;
+using content::BrowserThread;
+
+namespace {
+
+// helpers based on implementation in chrome_url_request_util.cc:
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+void DetermineCharset(const std::string &mime_type,
+                      const base::RefCountedMemory *data,
+                      std::string *out_charset)
+{
+    if (base::StartsWith(mime_type, "text/", base::CompareCase::INSENSITIVE_ASCII)) {
+        // All of our HTML files should be UTF-8 and for other resource types
+        // (like images), charset doesn't matter.
+        DCHECK(base::IsStringUTF8(base::StringPiece(reinterpret_cast<const char*>(data->front()), data->size())));
+        *out_charset = "utf-8";
+    }
+}
+
+// A request for an extension resource in a Chrome .pak file. These are used
+// by component extensions.
+class URLRequestResourceBundleJob : public net::URLRequestSimpleJob {
+public:
+    URLRequestResourceBundleJob(net::URLRequest *request,
+                                net::NetworkDelegate *network_delegate,
+                                const base::FilePath &filename,
+                                int resource_id,
+                                const std::string &content_security_policy,
+                                bool send_cors_header)
+            : net::URLRequestSimpleJob(request, network_delegate)
+            , filename_(filename)
+            , resource_id_(resource_id)
+            , weak_factory_(this)
+    {
+        // Leave cache headers out of resource bundle requests.
+        response_info_.headers = extensions::BuildHttpHeaders(content_security_policy, send_cors_header, base::Time());
+    }
+    int GetRefCountedData(std::string* mime_type,
+                          std::string* charset,
+                          scoped_refptr<base::RefCountedMemory>* data,
+                          net::CompletionOnceCallback callback) const override
+    {
+        const ui::ResourceBundle& rb = ui::ResourceBundle::GetSharedInstance();
+        *data = rb.LoadDataResourceBytes(resource_id_);
+
+        // Add the Content-Length header now that we know the resource length.
+        response_info_.headers->AddHeader(
+                    base::StringPrintf("%s: %s", net::HttpRequestHeaders::kContentLength,
+                                       base::NumberToString((*data)->size()).c_str()));
+
+        std::string* read_mime_type = new std::string;
+        base::PostTaskWithTraitsAndReplyWithResult(
+            FROM_HERE, {base::MayBlock()},
+            base::BindOnce(&net::GetMimeTypeFromFile, filename_,
+                           base::Unretained(read_mime_type)),
+            base::BindOnce(&URLRequestResourceBundleJob::OnMimeTypeRead,
+                           weak_factory_.GetWeakPtr(), mime_type, charset, *data,
+                           base::Owned(read_mime_type), std::move(callback)));
+
+        return net::ERR_IO_PENDING;
+    }
+
+    void GetResponseInfo(net::HttpResponseInfo* info) override
+    {
+        *info = response_info_;
+    }
+
+private:
+    ~URLRequestResourceBundleJob() override {}
+
+    void OnMimeTypeRead(std::string *out_mime_type,
+                        std::string *charset,
+                        scoped_refptr<base::RefCountedMemory> data,
+                        std::string *read_mime_type,
+                        net::CompletionOnceCallback callback,
+                        bool read_result)
+    {
+        response_info_.headers->AddHeader(
+                    base::StringPrintf("%s: %s", net::HttpRequestHeaders::kContentType,
+                                       read_mime_type->c_str()));
+        *out_mime_type = *read_mime_type;
+        DetermineCharset(*read_mime_type, data.get(), charset);
+        int result = read_result ? net::OK : net::ERR_INVALID_URL;
+        std::move(callback).Run(result);
+    }
+
+    // We need the filename of the resource to determine the mime type.
+    base::FilePath filename_;
+
+    // The resource bundle id to load.
+    int resource_id_;
+
+    net::HttpResponseInfo response_info_;
+
+    mutable base::WeakPtrFactory<URLRequestResourceBundleJob> weak_factory_;
+};
+
+} // namespace
+
+namespace extensions {
+
+ExtensionsBrowserClientQt::ExtensionsBrowserClientQt()
+    : api_client_(new ExtensionsAPIClientQt)
+    , resource_manager_(new ComponentExtensionResourceManagerQt)
+{
+    AddAPIProvider(std::make_unique<CoreExtensionsBrowserAPIProvider>());
+    AddAPIProvider(std::make_unique<ExtensionsBrowserAPIProviderQt>());
+}
+
+ExtensionsBrowserClientQt::~ExtensionsBrowserClientQt()
+{
+}
+
+bool ExtensionsBrowserClientQt::IsShuttingDown()
+{
+    return false;
+}
+
+bool ExtensionsBrowserClientQt::AreExtensionsDisabled(const base::CommandLine &command_line, BrowserContext *context)
+{
+    return false;
+}
+
+bool ExtensionsBrowserClientQt::IsValidContext(BrowserContext *context)
+{
+    return true;
+}
+
+bool ExtensionsBrowserClientQt::IsSameContext(BrowserContext *first,
+                                              BrowserContext *second)
+{
+    return first == second;
+}
+
+bool ExtensionsBrowserClientQt::HasOffTheRecordContext(BrowserContext *context)
+{
+    return false;
+}
+
+BrowserContext *ExtensionsBrowserClientQt::GetOffTheRecordContext(BrowserContext *context)
+{
+    // TODO(extensions): Do we need to support this?
+    return nullptr;
+}
+
+BrowserContext *ExtensionsBrowserClientQt::GetOriginalContext(BrowserContext *context)
+{
+    return context;
+}
+
+bool ExtensionsBrowserClientQt::IsGuestSession(BrowserContext *context) const
+{
+    return false;
+}
+
+bool ExtensionsBrowserClientQt::IsExtensionIncognitoEnabled(const std::string &extension_id,
+                                                            content::BrowserContext *context) const
+{
+    return false;
+}
+
+bool ExtensionsBrowserClientQt::CanExtensionCrossIncognito(const Extension *extension,
+                                                           content::BrowserContext *context) const
+{
+    return false;
+}
+
+net::URLRequestJob *ExtensionsBrowserClientQt::MaybeCreateResourceBundleRequestJob(net::URLRequest *request,
+                                                                                   net::NetworkDelegate *network_delegate,
+                                                                                   const base::FilePath &directory_path,
+                                                                                   const std::string &content_security_policy,
+                                                                                   bool send_cors_header)
+{
+    base::FilePath resources_path;
+    base::FilePath relative_path;
+    // Try to load extension resources from chrome resource file if
+    // directory_path is a descendant of resources_path. resources_path
+    // corresponds to src/chrome/browser/resources in source tree.
+    if (base::PathService::Get(base::DIR_QT_LIBRARY_DATA, &resources_path) &&
+            // Since component extension resources are included in
+            // component_extension_resources.pak file in resources_path, calculate
+            // extension relative path against resources_path.
+            resources_path.AppendRelativePath(directory_path, &relative_path)) {
+        base::FilePath request_path = extensions::file_util::ExtensionURLToRelativeFilePath(request->url());
+        int resource_id = 0;
+        if (GetComponentExtensionResourceManager()->IsComponentExtensionResource(directory_path, request_path, &resource_id)) {
+            relative_path = relative_path.Append(request_path);
+            relative_path = relative_path.NormalizePathSeparators();
+            return new URLRequestResourceBundleJob(request,
+                                                   network_delegate,
+                                                   relative_path,
+                                                   resource_id,
+                                                   content_security_policy,
+                                                   send_cors_header);
+        }
+    }
+    return nullptr;
+}
+
+// Return the resource relative path and id for the given request.
+base::FilePath ExtensionsBrowserClientQt::GetBundleResourcePath(const network::ResourceRequest &request,
+                                                                const base::FilePath &extension_resources_path,
+                                                                int *resource_id) const
+{
+    *resource_id = 0;
+    // |chrome_resources_path| corresponds to src/chrome/browser/resources in
+    // source tree.
+    base::FilePath resources_path;
+    if (!base::PathService::Get(base::DIR_QT_LIBRARY_DATA, &resources_path))
+        return base::FilePath();
+
+    // Since component extension resources are included in
+    // component_extension_resources.pak file in |chrome_resources_path|,
+    // calculate the extension |request_relative_path| against
+    // |chrome_resources_path|.
+    if (!resources_path.IsParent(extension_resources_path))
+        return base::FilePath();
+
+    const base::FilePath request_relative_path =
+            extensions::file_util::ExtensionURLToRelativeFilePath(request.url);
+    if (!ExtensionsBrowserClient::Get()->GetComponentExtensionResourceManager()->IsComponentExtensionResource(
+                extension_resources_path, request_relative_path, resource_id)) {
+        return base::FilePath();
+    }
+    DCHECK_NE(0, *resource_id);
+
+    return request_relative_path;
+}
+
+// Creates and starts a URLLoader to load an extension resource from the
+// embedder's resource bundle (.pak) files. Used for component extensions.
+void ExtensionsBrowserClientQt::LoadResourceFromResourceBundle(const network::ResourceRequest &request,
+                                                               network::mojom::URLLoaderRequest loader,
+                                                               const base::FilePath &resource_relative_path,
+                                                               int resource_id,
+                                                               const std::string &content_security_policy,
+                                                               network::mojom::URLLoaderClientPtr client,
+                                                               bool send_cors_header)
+{
+    NOTIMPLEMENTED();
+}
+
+
+bool ExtensionsBrowserClientQt::AllowCrossRendererResourceLoad(const GURL &url,
+                                                               content::ResourceType resource_type,
+                                                               ui::PageTransition page_transition,
+                                                               int child_id,
+                                                               bool is_incognito,
+                                                               const Extension *extension,
+                                                               const ExtensionSet &extensions,
+                                                               const ProcessMap &process_map)
+{
+
+    if (extension && extension->id() == extension_misc::kPdfExtensionId)
+        return true;
+
+    bool allowed = false;
+    if (url_request_util::AllowCrossRendererResourceLoad(url, resource_type,
+                                                         page_transition, child_id,
+                                                         is_incognito, extension, extensions,
+                                                         process_map, &allowed)) {
+        return allowed;
+    }
+    // Couldn't determine if resource is allowed. Block the load.
+    return false;
+}
+
+PrefService *ExtensionsBrowserClientQt::GetPrefServiceForContext(BrowserContext *context)
+{
+    return static_cast<Profile *>(context)->GetPrefs();
+}
+
+void ExtensionsBrowserClientQt::GetEarlyExtensionPrefsObservers(content::BrowserContext *context,
+                                                                std::vector<ExtensionPrefsObserver *> *observers) const
+{
+}
+
+ProcessManagerDelegate *ExtensionsBrowserClientQt::GetProcessManagerDelegate() const
+{
+    return nullptr;
+}
+
+std::unique_ptr<ExtensionHostDelegate> ExtensionsBrowserClientQt::CreateExtensionHostDelegate()
+{
+    // TODO(extensions): Implement to support Apps.
+    NOTREACHED();
+    return std::unique_ptr<ExtensionHostDelegate>();
+}
+
+bool ExtensionsBrowserClientQt::DidVersionUpdate(BrowserContext *context)
+{
+    // TODO(jamescook): We might want to tell extensions when app_shell updates.
+    return false;
+}
+
+void ExtensionsBrowserClientQt::PermitExternalProtocolHandler()
+{
+}
+
+bool ExtensionsBrowserClientQt::IsRunningInForcedAppMode()
+{
+    return false;
+}
+
+bool ExtensionsBrowserClientQt::IsLoggedInAsPublicAccount()
+{
+    return false;
+}
+
+ExtensionSystemProvider *ExtensionsBrowserClientQt::GetExtensionSystemFactory()
+{
+    return ExtensionSystemFactoryQt::GetInstance();
+}
+
+// void ExtensionsBrowserClientQt::RegisterExtensionFunctions(ExtensionFunctionRegistry *registry) const
+//{
+//    // Register core extension-system APIs.
+//    api::GeneratedFunctionRegistry::RegisterAll(registry);
+//}
+
+void ExtensionsBrowserClientQt::RegisterExtensionInterfaces(service_manager::BinderRegistryWithArgs<content::RenderFrameHost *> *registry,
+                                                            content::RenderFrameHost *render_frame_host,
+                                                            const Extension *extension) const
+{
+    RegisterInterfacesForExtension(registry, render_frame_host, extension);
+}
+
+std::unique_ptr<RuntimeAPIDelegate> ExtensionsBrowserClientQt::CreateRuntimeAPIDelegate(content::BrowserContext *context) const
+{
+    // TODO(extensions): Implement to support Apps.
+    NOTREACHED();
+    return std::unique_ptr<RuntimeAPIDelegate>();
+}
+
+const ComponentExtensionResourceManager *ExtensionsBrowserClientQt::GetComponentExtensionResourceManager()
+{
+    return resource_manager_.get();
+}
+
+void ExtensionsBrowserClientQt::BroadcastEventToRenderers(events::HistogramValue histogram_value,
+                                                          const std::string &event_name,
+                                                          std::unique_ptr<base::ListValue> args)
+{
+    NOTIMPLEMENTED();
+    // TODO : do the event routing
+    // event_router_forwarder_->BroadcastEventToRenderers(
+    //     histogram_value, event_name, std::move(args), GURL());
+}
+
+net::NetLog *ExtensionsBrowserClientQt::GetNetLog()
+{
+    return nullptr;
+}
+
+ExtensionCache *ExtensionsBrowserClientQt::GetExtensionCache()
+{
+    // Only used by Chrome via ExtensionService.
+    NOTREACHED();
+    return nullptr;
+}
+
+bool ExtensionsBrowserClientQt::IsBackgroundUpdateAllowed()
+{
+    return true;
+}
+
+bool ExtensionsBrowserClientQt::IsMinBrowserVersionSupported(
+        const std::string &min_version)
+{
+    return true;
+}
+
+bool ExtensionsBrowserClientQt::IsLockScreenContext(content::BrowserContext *context)
+{
+    return false;
+}
+
+// Returns the locale used by the application.
+std::string ExtensionsBrowserClientQt::GetApplicationLocale()
+{
+    return WebEngineLibraryInfo::getApplicationLocale();
+}
+
+bool ExtensionsBrowserClientQt::IsAppModeForcedForApp(const ExtensionId &id)
+{
+    return false;
+}
+
+bool ExtensionsBrowserClientQt::IsInDemoMode()
+{
+    return false;
+}
+
+ExtensionWebContentsObserver *ExtensionsBrowserClientQt::GetExtensionWebContentsObserver(content::WebContents *web_contents)
+{
+    return ExtensionWebContentsObserverQt::FromWebContents(web_contents);
+}
+
+KioskDelegate *ExtensionsBrowserClientQt::GetKioskDelegate()
+{
+    NOTREACHED();
+    return nullptr;
+}
+
+bool ExtensionsBrowserClientQt::IsScreensaverInDemoMode(const std::string& app_id)
+{
+    return false;
+}
+
+void ExtensionsBrowserClientQt::SetAPIClientForTest(ExtensionsAPIClient *api_client)
+{
+    api_client_.reset(api_client);
+}
+
+} // namespace extensions
diff --git a/src/core/extensions/extensions_browser_client_qt.h b/src/core/extensions/extensions_browser_client_qt.h
new file mode 100644
index 000000000..f766b96a7
--- /dev/null
+++ b/src/core/extensions/extensions_browser_client_qt.h
@@ -0,0 +1,161 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2015 The Chromium Embedded Framework Authors.
+// Portions copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef EXTENSIONS_BROWSER_CLIENT_QT_H_
+#define EXTENSIONS_BROWSER_CLIENT_QT_H_
+
+#include "base/compiler_specific.h"
+#include "extensions/browser/extensions_browser_client.h"
+
+namespace extensions {
+
+class ExtensionsAPIClient;
+
+// An ExtensionsBrowserClient that supports a single content::BrowserContent
+// with no related incognito context.
+class ExtensionsBrowserClientQt : public ExtensionsBrowserClient
+{
+public:
+    ExtensionsBrowserClientQt();
+    ~ExtensionsBrowserClientQt() override;
+
+    // ExtensionsBrowserClient overrides:
+    bool IsShuttingDown() override;
+    bool AreExtensionsDisabled(const base::CommandLine &command_line,
+                               content::BrowserContext *context) override;
+    bool IsValidContext(content::BrowserContext *context) override;
+    bool IsSameContext(content::BrowserContext *first,
+                       content::BrowserContext *second) override;
+    bool HasOffTheRecordContext(content::BrowserContext *context) override;
+    content::BrowserContext *GetOffTheRecordContext(content::BrowserContext *context) override;
+    content::BrowserContext *GetOriginalContext(content::BrowserContext *context) override;
+    bool IsGuestSession(content::BrowserContext *context) const override;
+    bool IsExtensionIncognitoEnabled(const std::string &extension_id, content::BrowserContext *context) const override;
+    bool CanExtensionCrossIncognito(const Extension *extension, content::BrowserContext *context) const override;
+    net::URLRequestJob *MaybeCreateResourceBundleRequestJob(net::URLRequest *request,
+                                                            net::NetworkDelegate *network_delegate,
+                                                            const base::FilePath &directory_path,
+                                                            const std::string &content_security_policy,
+                                                            bool send_cors_header) override;
+    bool AllowCrossRendererResourceLoad(const GURL &url,
+                                        content::ResourceType resource_type,
+                                        ui::PageTransition page_transition,
+                                        int child_id,
+                                        bool is_incognito,
+                                        const Extension *extension,
+                                        const ExtensionSet &extensions,
+                                        const ProcessMap &process_map) override;
+    PrefService *GetPrefServiceForContext(content::BrowserContext *context) override;
+    void GetEarlyExtensionPrefsObservers(content::BrowserContext *context, std::vector<ExtensionPrefsObserver *> *observers) const
+            override;
+    ProcessManagerDelegate *GetProcessManagerDelegate() const override;
+    std::unique_ptr<ExtensionHostDelegate>
+    CreateExtensionHostDelegate() override;
+    bool DidVersionUpdate(content::BrowserContext *context) override;
+    void PermitExternalProtocolHandler() override;
+    bool IsRunningInForcedAppMode() override;
+    bool IsLoggedInAsPublicAccount() override;
+    ExtensionSystemProvider *GetExtensionSystemFactory() override;
+//    void RegisterExtensionFunctions(ExtensionFunctionRegistry *registry) const;
+    std::unique_ptr<RuntimeAPIDelegate> CreateRuntimeAPIDelegate(content::BrowserContext *context) const override;
+    void RegisterExtensionInterfaces(service_manager::BinderRegistryWithArgs<content::RenderFrameHost *> *registry,
+                                     content::RenderFrameHost *render_frame_host,
+                                     const Extension *extension) const override;
+    const ComponentExtensionResourceManager *
+    GetComponentExtensionResourceManager() override;
+    void BroadcastEventToRenderers(events::HistogramValue histogram_value,
+                                   const std::string &event_name,
+                                   std::unique_ptr<base::ListValue> args) override;
+    net::NetLog *GetNetLog() override;
+    ExtensionCache *GetExtensionCache() override;
+    bool IsBackgroundUpdateAllowed() override;
+    bool IsMinBrowserVersionSupported(const std::string &min_version) override;
+    ExtensionWebContentsObserver *GetExtensionWebContentsObserver(
+            content::WebContents *web_contents) override;
+    KioskDelegate *GetKioskDelegate() override;
+
+    // Whether the browser context is associated with Chrome OS lock screen.
+    bool IsLockScreenContext(content::BrowserContext *context) override;
+
+    bool IsAppModeForcedForApp(const ExtensionId &id) override;
+    bool IsInDemoMode() override;
+
+    // Return the resource relative path and id for the given request.
+    base::FilePath GetBundleResourcePath(const network::ResourceRequest &request,
+                                         const base::FilePath &extension_resources_path,
+                                         int *resource_id) const override;
+
+    // Creates and starts a URLLoader to load an extension resource from the
+    // embedder's resource bundle (.pak) files. Used for component extensions.
+    void LoadResourceFromResourceBundle(const network::ResourceRequest &request,
+                                        network::mojom::URLLoaderRequest loader,
+                                        const base::FilePath &resource_relative_path,
+                                        int resource_id,
+                                        const std::string &content_security_policy,
+                                        network::mojom::URLLoaderClientPtr client,
+                                        bool send_cors_header) override;
+
+    // Returns the locale used by the application.
+    std::string GetApplicationLocale() override;
+
+    bool IsScreensaverInDemoMode(const std::string& app_id) override;
+
+    // Sets the API client.
+    void SetAPIClientForTest(ExtensionsAPIClient *api_client);
+
+private:
+    // Support for extension APIs.
+    std::unique_ptr<ExtensionsAPIClient> api_client_;
+
+    // Resource manager used to supply resources from pak files.
+    std::unique_ptr<ComponentExtensionResourceManager> resource_manager_;
+
+    //scoped_refptr<EventRouterForwarder> event_router_forwarder_;
+
+    DISALLOW_COPY_AND_ASSIGN(ExtensionsBrowserClientQt);
+};
+
+} // namespace extensions
+
+#endif // EXTENSIONS_BROWSER_CLIENT_QT_H_
diff --git a/src/core/extensions/mime_handler_view_guest_delegate_qt.cpp b/src/core/extensions/mime_handler_view_guest_delegate_qt.cpp
new file mode 100644
index 000000000..438b8a83e
--- /dev/null
+++ b/src/core/extensions/mime_handler_view_guest_delegate_qt.cpp
@@ -0,0 +1,78 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2015 The Chromium Embedded Framework Authors.
+// Portions copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "mime_handler_view_guest_delegate_qt.h"
+
+#include "content/browser/browser_plugin/browser_plugin_guest.h"
+#include "content/browser/web_contents/web_contents_impl.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/common/context_menu_params.h"
+#include "extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest.h"
+
+namespace extensions {
+
+MimeHandlerViewGuestDelegateQt::MimeHandlerViewGuestDelegateQt(MimeHandlerViewGuest *guest)
+    : MimeHandlerViewGuestDelegate()
+{
+}
+
+MimeHandlerViewGuestDelegateQt::~MimeHandlerViewGuestDelegateQt()
+{
+}
+
+bool MimeHandlerViewGuestDelegateQt::HandleContextMenu(content::WebContents *web_contents, const content::ContextMenuParams &params)
+{
+    content::ContextMenuParams new_params = params;
+
+    gfx::Point guest_coordinates =
+            static_cast<content::WebContentsImpl *>(web_contents)->GetBrowserPluginGuest()->GetScreenCoordinates(gfx::Point());
+
+    // Adjust (x,y) position for offset from guest to embedder.
+    new_params.x += guest_coordinates.x();
+    new_params.y += guest_coordinates.y();
+
+    return false;
+}
+
+} // namespace extensions
diff --git a/src/core/extensions/mime_handler_view_guest_delegate_qt.h b/src/core/extensions/mime_handler_view_guest_delegate_qt.h
new file mode 100644
index 000000000..b679c7a38
--- /dev/null
+++ b/src/core/extensions/mime_handler_view_guest_delegate_qt.h
@@ -0,0 +1,76 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Portions copyright 2015 The Chromium Embedded Framework Authors.
+// Portions copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef MIME_HANDLER_VIEW_GUEST_DELEGATE_QT_H_
+#define MIME_HANDLER_VIEW_GUEST_DELEGATE_QT_H_
+
+#include "extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest_delegate.h"
+#include "content/browser/web_contents/web_contents_view.h"
+#include "content/public/browser/web_contents.h"
+
+namespace content {
+struct ContextMenuParams;
+}
+
+namespace extensions {
+class MimeHandlerViewGuest;
+
+class MimeHandlerViewGuestDelegateQt : public MimeHandlerViewGuestDelegate
+{
+public:
+    explicit MimeHandlerViewGuestDelegateQt(MimeHandlerViewGuest *guest);
+    ~MimeHandlerViewGuestDelegateQt() override;
+
+    bool HandleContextMenu(content::WebContents *web_contents,
+                           const content::ContextMenuParams &params) override;
+
+private:
+    MimeHandlerViewGuest *guest_; // Owns us.
+
+    DISALLOW_COPY_AND_ASSIGN(MimeHandlerViewGuestDelegateQt);
+};
+
+} // namespace extensions
+
+#endif // MIME_HANDLER_VIEW_GUEST_DELEGATE_QT_H_
diff --git a/src/core/extensions/pdf_web_contents_helper_client_qt.h b/src/core/extensions/pdf_web_contents_helper_client_qt.h
new file mode 100644
index 000000000..a22feb138
--- /dev/null
+++ b/src/core/extensions/pdf_web_contents_helper_client_qt.h
@@ -0,0 +1,29 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef PDF_WEB_CONTENTS_HELPER_CLIENT_QT_H_
+#define PDF_WEB_CONTENTS_HELPER_CLIENT_QT_H_
+
+#include "base/macros.h"
+#include "components/pdf/browser/pdf_web_contents_helper_client.h"
+
+namespace extensions {
+
+class PDFWebContentsHelperClientQt : public pdf::PDFWebContentsHelperClient {
+public:
+    PDFWebContentsHelperClientQt();
+    ~PDFWebContentsHelperClientQt() override;
+
+private:
+    // pdf::PDFWebContentsHelperClient:
+    void UpdateContentRestrictions(content::WebContents* contents, int content_restrictions) override;
+    void OnPDFHasUnsupportedFeature(content::WebContents* contents) override;
+    void OnSaveURL(content::WebContents* contents) override;
+
+    DISALLOW_COPY_AND_ASSIGN(PDFWebContentsHelperClientQt);
+};
+
+}  // namespace extensions
+
+#endif  // PDF_WEB_CONTENTS_HELPER_CLIENT_QT_H_
diff --git a/src/core/login_delegate_qt.cpp b/src/core/login_delegate_qt.cpp
index 31824ca71..5b407c094 100644
--- a/src/core/login_delegate_qt.cpp
+++ b/src/core/login_delegate_qt.cpp
@@ -50,10 +50,22 @@
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/resource_dispatcher_host.h"
 #include "content/public/browser/resource_request_info.h"
+#include "content/public/browser/stream_info.h"
+#include "extensions/buildflags/buildflags.h"
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/browser/info_map.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/manifest_handlers/mime_types_handler.h"
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
 #include "net/url_request/url_request.h"
 
 #include "authentication_dialog_controller.h"
 #include "authentication_dialog_controller_p.h"
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/extension_system_qt.h"
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+#include "resource_context_qt.h"
 #include "type_conversion.h"
 #include "web_contents_view_qt.h"
 
diff --git a/src/core/profile_adapter.cpp b/src/core/profile_adapter.cpp
index dfe701cc9..48a6906e9 100644
--- a/src/core/profile_adapter.cpp
+++ b/src/core/profile_adapter.cpp
@@ -58,6 +58,10 @@
 
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/browser/extension_system.h"
+#endif
+
 #include <QCoreApplication>
 #include <QDir>
 #include <QString>
@@ -93,6 +97,10 @@ ProfileAdapter::ProfileAdapter(const QString &storageName):
     // fixme: this should not be here
     m_profile->m_profileIOData->initializeOnUIThread();
     m_customUrlSchemeHandlers.insert(QByteArrayLiteral("qrc"), &m_qrcHandler);
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    if (!storageName.isEmpty())
+        extensions::ExtensionSystem::Get(m_profile.data())->InitForRegularProfile(true);
+#endif
 }
 
 ProfileAdapter::~ProfileAdapter()
diff --git a/src/core/profile_io_data_qt.cpp b/src/core/profile_io_data_qt.cpp
index dc5b6624e..4815b8749 100644
--- a/src/core/profile_io_data_qt.cpp
+++ b/src/core/profile_io_data_qt.cpp
@@ -223,6 +223,13 @@ content::ResourceContext *ProfileIODataQt::resourceContext()
     return m_resourceContext.get();
 }
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+extensions::ExtensionSystemQt* ProfileIODataQt::GetExtensionSystem()
+{
+    return m_profile->GetExtensionSystem();
+}
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
 void ProfileIODataQt::initializeOnIOThread()
 {
     m_networkDelegate.reset(new NetworkDelegateQt(this));
diff --git a/src/core/profile_io_data_qt.h b/src/core/profile_io_data_qt.h
index f3460935a..407d0d6f2 100644
--- a/src/core/profile_io_data_qt.h
+++ b/src/core/profile_io_data_qt.h
@@ -43,6 +43,7 @@
 #include "profile_adapter.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
+#include "extensions/buildflags/buildflags.h"
 #include "services/proxy_resolver/public/mojom/proxy_resolver.mojom.h"
 
 #include <QtCore/QString>
@@ -61,6 +62,10 @@ class URLRequestJobFactoryImpl;
 class TransportSecurityPersister;
 }
 
+namespace extensions {
+class ExtensionSystemQt;
+}
+
 namespace QtWebEngineCore {
 
 class ProfileQt;
@@ -78,6 +83,10 @@ public:
     QPointer<ProfileAdapter> profileAdapter();
     content::ResourceContext *resourceContext();
     net::URLRequestContext *urlRequestContext();
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionSystemQt* GetExtensionSystem();
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
     void initializeOnIOThread();
     void initializeOnUIThread(); // runs on ui thread
     void shutdownOnUIThread(); // runs on ui thread
diff --git a/src/core/profile_qt.cpp b/src/core/profile_qt.cpp
index d98bb5c9c..0ede1df55 100644
--- a/src/core/profile_qt.cpp
+++ b/src/core/profile_qt.cpp
@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2018 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the QtWebEngine module of the Qt Toolkit.
@@ -71,11 +71,24 @@
 #include "components/spellcheck/browser/pref_names.h"
 #endif
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "components/guest_view/browser/guest_view_manager.h"
+#include "extensions/browser/extension_protocols.h"
+#include "extensions/browser/pref_names.h"
+#include "extensions/browser/process_manager.h"
+#include "extensions/common/constants.h"
+
+#include "extensions/extension_system_qt.h"
+#endif
+
 namespace QtWebEngineCore {
 
 ProfileQt::ProfileQt(ProfileAdapter *profileAdapter)
     : m_profileIOData(new ProfileIODataQt(this)),
       m_profileAdapter(profileAdapter)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    , m_extensionSystem(nullptr)
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
 {
     PrefServiceFactory factory;
     factory.set_user_prefs(new InMemoryPrefStore);
@@ -94,6 +107,23 @@ ProfileQt::ProfileQt(ProfileAdapter *profileAdapter)
 #endif // QT_CONFIG(webengine_spellchecker)
     registry->RegisterBooleanPref(prefs::kShowInternalAccessibilityTree, false);
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    registry->RegisterDictionaryPref(extensions::pref_names::kExtensions);
+    registry->RegisterListPref(extensions::pref_names::kInstallAllowList);
+    registry->RegisterListPref(extensions::pref_names::kInstallDenyList);
+    registry->RegisterDictionaryPref(extensions::pref_names::kInstallForceList);
+    registry->RegisterDictionaryPref(extensions::pref_names::kInstallLoginScreenAppList);
+    registry->RegisterListPref(extensions::pref_names::kAllowedTypes);
+    registry->RegisterBooleanPref(extensions::pref_names::kStorageGarbageCollect, false);
+    registry->RegisterInt64Pref(extensions::pref_names::kLastUpdateCheck, 0);
+    registry->RegisterInt64Pref(extensions::pref_names::kNextUpdateCheck, 0);
+    registry->RegisterListPref(extensions::pref_names::kAllowedInstallSites);
+    registry->RegisterStringPref(extensions::pref_names::kLastChromeVersion, std::string());
+    registry->RegisterListPref(extensions::pref_names::kNativeMessagingBlacklist);
+    registry->RegisterListPref(extensions::pref_names::kNativeMessagingWhitelist);
+    registry->RegisterBooleanPref(extensions::pref_names::kNativeMessagingUserLevelHosts, true);
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
     m_prefService = factory.Create(registry);
     user_prefs::UserPrefs::Set(this, m_prefService.get());
 
@@ -102,6 +132,11 @@ ProfileQt::ProfileQt(ProfileAdapter *profileAdapter)
     // ProfileQt object is allocated at the same address as a previously
     // destroyed one. Needs to be called after WebEngineContext initialization.
     BrowserContextDependencyManager::GetInstance()->MarkBrowserContextLive(this);
+
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    m_extensionSystem = static_cast<extensions::ExtensionSystemQt*>(extensions::ExtensionSystem::Get(this));
+    m_extensionSystem->InitForRegularProfile(true);
+#endif
 }
 
 ProfileQt::~ProfileQt()
@@ -168,7 +203,9 @@ content::DownloadManagerDelegate *ProfileQt::GetDownloadManagerDelegate()
 
 content::BrowserPluginGuestManager *ProfileQt::GetGuestManager()
 {
-    return nullptr;
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    return guest_view::GuestViewManager::FromBrowserContext(this);
+#endif
 }
 
 storage::SpecialStoragePolicy *ProfileQt::GetSpecialStoragePolicy()
@@ -222,6 +259,12 @@ net::URLRequestContextGetter *ProfileQt::CreateRequestContext(
 {
     DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
     DCHECK(!m_urlRequestContextGetter.get());
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::InfoMap* extension_info_map = GetExtensionSystem()->info_map();
+    (*protocol_handlers)[extensions::kExtensionScheme] =
+            extensions::CreateExtensionProtocolHandler(IsOffTheRecord(),extension_info_map);
+#endif
+
     m_profileIOData->setRequestContextData(protocol_handlers, std::move(request_interceptors));
     m_profileIOData->updateStorageSettings();
     m_urlRequestContextGetter = new URLRequestContextGetterQt(m_profileIOData.get());
@@ -278,4 +321,12 @@ bool ProfileQt::isSpellCheckEnabled() const
     return m_prefService->GetBoolean(spellcheck::prefs::kSpellCheckEnable);
 }
 #endif // QT_CONFIG(webengine_spellchecker)
+
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+extensions::ExtensionSystemQt* ProfileQt::GetExtensionSystem()
+{
+    return m_extensionSystem;
+}
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
 } // namespace QtWebEngineCore
diff --git a/src/core/profile_qt.h b/src/core/profile_qt.h
index 8641646b1..41eeeecf5 100644
--- a/src/core/profile_qt.h
+++ b/src/core/profile_qt.h
@@ -43,6 +43,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/resource_context.h"
+#include "extensions/buildflags/buildflags.h"
 #include "net/url_request/url_request_context.h"
 #include "profile_io_data_qt.h"
 #include <QtGlobal>
@@ -53,6 +54,10 @@ QT_END_NAMESPACE
 class InMemoryPrefStore;
 class PrefService;
 
+namespace extensions {
+class ExtensionSystemQt;
+}
+
 namespace QtWebEngineCore {
 
 class ProfileAdapter;
@@ -99,6 +104,7 @@ public:
     PrefService *GetPrefs() override;
     const PrefService *GetPrefs() const override;
     net::URLRequestContextGetter *GetRequestContext() override;
+    void Initialize();
 
     ProfileAdapter *profileAdapter() { return m_profileAdapter; }
 
@@ -109,6 +115,9 @@ public:
     void setSpellCheckEnabled(bool enabled);
     bool isSpellCheckEnabled() const;
 #endif
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionSystemQt* GetExtensionSystem();
+#endif // defined(ENABLE_EXTENSIONS)
 
 private:
     friend class ContentBrowserClientQt;
@@ -120,6 +129,10 @@ private:
     std::unique_ptr<ProfileIODataQt> m_profileIOData;
     ProfileAdapter *m_profileAdapter;
     friend class ProfileAdapter;
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionSystemQt *m_extensionSystem;
+#endif //ENABLE_EXTENSIONS
+    friend class BrowserContextAdapter;
 
     DISALLOW_COPY_AND_ASSIGN(ProfileQt);
 };
diff --git a/src/core/qtwebengine.gni b/src/core/qtwebengine.gni
index 0bb8f0cdb..7c0ca763e 100644
--- a/src/core/qtwebengine.gni
+++ b/src/core/qtwebengine.gni
@@ -1,5 +1,6 @@
 import("//build/config/ui.gni")
 import("//media/media_options.gni")
+import("//extensions/buildflags/buildflags.gni")
 import("//third_party/widevine/cdm/widevine.gni")
 
 chromium_version = exec_script("//build/util/version.py", [ "-f", rebase_path("//chrome/VERSION"),
@@ -38,7 +39,7 @@ deps = [
   "//ui/gl",
   "//qtwebengine/browser:interfaces",
   ":qtwebengine_sources",
-  ":qtwebengine_resources"
+  ":qtwebengine_resources",
 ]
 
 if (enable_webrtc) {
@@ -59,6 +60,12 @@ if (use_ozone) {
   ]
 }
 
+if (enable_extensions) {
+  deps += [
+    ":qtwebengine_extensions_features"
+  ]
+}
+
 data_deps = [ "//qtwebengine/browser:service_manifests" ]
 
 defines = [
diff --git a/src/core/qtwebengine_resources.gni b/src/core/qtwebengine_resources.gni
index 6e8c3c6eb..283235f66 100644
--- a/src/core/qtwebengine_resources.gni
+++ b/src/core/qtwebengine_resources.gni
@@ -1,10 +1,14 @@
 import("//tools/grit/repack.gni")
 import("//build/config/locales.gni")
 import("//chrome/chrome_repack_locales.gni")
+import("//extensions/buildflags/buildflags.gni")
 
 group("qtwebengine_resources") {
   deps = [
       "//chrome/app:generated_resources",
+      "//chrome/browser:resources",
+      "//chrome/browser/resources:component_extension_resources",
+      "//chrome/common:resources",
       "//components/resources:components_resources",
       ":qtwebengine_repack_resources",
       ":qtwebengine_repack_resources_100",
@@ -17,6 +21,8 @@ group("qtwebengine_resources") {
 repack("qtwebengine_repack_resources") {
   sources = [
     "$root_gen_dir/qtwebengine/qt_webengine_resources.pak",
+    "$root_gen_dir/chrome/browser_resources.pak",
+    "$root_gen_dir/chrome/common_resources.pak",
     "$root_gen_dir/chrome/quota_internals_resources.pak",
     "$root_gen_dir/chrome/task_scheduler_internals_resources.pak",
     "$root_gen_dir/components/components_resources.pak",
@@ -31,6 +37,8 @@ repack("qtwebengine_repack_resources") {
      "//qtwebengine/browser:qt_webengine_resources",
      "//chrome/browser/resources:quota_internals_resources",
      "//chrome/browser/resources:task_scheduler_internals_resources",
+     "//chrome/browser:resources_grit",
+     "//chrome/common:resources_grit",
      "//components/resources:components_resources_grit",
      "//content:resources_grit",
      "//mojo/public/js:resources",
@@ -38,6 +46,20 @@ repack("qtwebengine_repack_resources") {
      "//third_party/blink/public:resources_grit",
      "//ui/resources:webui_resources_grd_grit",
   ]
+
+  if (enable_extensions) {
+    sources += [
+      "$root_gen_dir/chrome/component_extension_resources.pak",
+      "$root_gen_dir/extensions/extensions_renderer_resources.pak",
+      "$root_gen_dir/extensions/extensions_resources.pak",
+    ]
+    deps += [
+      "//chrome/browser/resources:component_extension_resources_grit",
+      "//extensions:extensions_renderer_resources_grit",
+      "//extensions:extensions_resources_grd_grit",
+    ]
+  }
+
 }
 
 repack("qtwebengine_repack_resources_100") {
@@ -56,6 +78,14 @@ repack("qtwebengine_repack_resources_100") {
     "//third_party/blink/public:scaled_resources_100_percent",
     "//ui/resources:ui_resources_grd_grit"
   ]
+  if (enable_extensions) {
+    sources += [
+      "$root_gen_dir/extensions/extensions_browser_resources_100_percent.pak"
+    ]
+    deps += [
+      "//extensions:extensions_browser_resources_grit"
+    ]
+  }
 }
 
 repack("qtwebengine_repack_resources_200") {
@@ -74,6 +104,14 @@ repack("qtwebengine_repack_resources_200") {
     "//third_party/blink/public:scaled_resources_200_percent",
     "//ui/resources:ui_resources_grd_grit"
   ]
+  if (enable_extensions) {
+    sources += [
+      "$root_gen_dir/extensions/extensions_browser_resources_200_percent.pak"
+    ]
+    deps += [
+      "//extensions:extensions_browser_resources_grit"
+    ]
+  }
 }
 
 repack("qtwebengine_repack_resources_devtools") {
diff --git a/src/core/qtwebengine_sources.gni b/src/core/qtwebengine_sources.gni
index aa9d12480..58df7096b 100644
--- a/src/core/qtwebengine_sources.gni
+++ b/src/core/qtwebengine_sources.gni
@@ -1,9 +1,11 @@
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
+import("//chrome/common/features.gni")
 import("//components/spellcheck/spellcheck_build_features.gni")
 import("//pdf/features.gni")
 import("//ppapi/buildflags/buildflags.gni")
 import("//printing/buildflags/buildflags.gni")
+import("//extensions/buildflags/buildflags.gni")
 
 source_set("qtwebengine_spellcheck_sources") {
   include_dirs = core_include_dirs
@@ -40,12 +42,14 @@ source_set("qtwebengine_sources") {
     "//skia:skia_config",
     "//third_party/boringssl:external_config",
   ]
+
   deps = [
     "//chrome/common:buildflags",
     "//components/nacl/common:buildflags",
     "//extensions/buildflags:buildflags",
     "//third_party/blink/public/mojom:mojom_platform",
   ]
+
   sources = [
     "//chrome/browser/accessibility/accessibility_ui.cc",
     "//chrome/browser/accessibility/accessibility_ui.h",
@@ -80,12 +84,47 @@ source_set("qtwebengine_sources") {
     "//chrome/common/url_constants.h",
     "//chrome/common/webui_url_constants.cc",
     "//chrome/common/webui_url_constants.h",
-    "//extensions/common/constants.cc",
-    "//extensions/common/constants.h",
-    "//extensions/common/url_pattern.cc",
-    "//extensions/common/url_pattern.h",
+    "//components/prefs/in_memory_pref_store.cc",
+    "//components/prefs/in_memory_pref_store.h",
   ]
 
+  if (enable_extensions) {
+    deps += [
+      ":qtwebengine_extensions_features",
+      "//chrome/browser/resources:component_extension_resources_grit",
+      "//chrome/common/extensions/api",
+      "//chrome/common/extensions/api:extensions_features",
+      "//components/crx_file",
+      "//components/crx_file:crx_creator",
+      "//components/spellcheck:buildflags",
+      "//extensions/buildflags:buildflags",
+      "//extensions/common",
+      "//extensions/common/api",
+      "//extensions/common:core_api_provider",
+      "//extensions/browser",
+      "//extensions/browser/api",
+      "//extensions/browser:core_api_provider",
+      "//extensions/renderer",
+      "//extensions:extensions_resources",
+      "//extensions/strings",
+    ]
+    sources += [
+      "//chrome/common/extensions/permissions/chrome_api_permissions.cc",
+      "//chrome/common/extensions/permissions/chrome_api_permissions.h",
+      "//chrome/common/extensions/permissions/chrome_permission_message_provider.cc",
+      "//chrome/common/extensions/permissions/chrome_permission_message_provider.h",
+      "//chrome/common/extensions/permissions/chrome_permission_message_rules.cc",
+      "//chrome/common/extensions/permissions/chrome_permission_message_rules.h",
+    ]
+  } else {
+    sources += [
+      "//extensions/common/constants.cc",
+      "//extensions/common/constants.h",
+      "//extensions/common/url_pattern.cc",
+      "//extensions/common/url_pattern.h",
+    ]
+  }
+
   if (is_linux) {
     sources += [
       "//chrome/browser/ui/webui/sandbox_internals_ui.cc",
@@ -131,6 +170,8 @@ source_set("qtwebengine_sources") {
       deps += [
          "//pdf",
          "//pdf:buildflags",
+         "//components/pdf/browser:browser",
+         "//components/pdf/renderer:renderer",
          "//components/printing/browser",
          "//components/printing/renderer",
       ]
diff --git a/src/core/render_widget_host_view_qt.cpp b/src/core/render_widget_host_view_qt.cpp
index ac7357f0e..0217bed59 100644
--- a/src/core/render_widget_host_view_qt.cpp
+++ b/src/core/render_widget_host_view_qt.cpp
@@ -188,14 +188,13 @@ static inline bool isCommonTextEditShortcut(const QKeyEvent *ke)
 static uint32_t s_eventId = 0;
 class MotionEventQt : public ui::MotionEvent {
 public:
-    MotionEventQt(const QList<QTouchEvent::TouchPoint> &touchPoints, const base::TimeTicks &eventTime, Action action, const Qt::KeyboardModifiers modifiers, float dpiScale, int index = -1)
+    MotionEventQt(const QList<QTouchEvent::TouchPoint> &touchPoints, const base::TimeTicks &eventTime, Action action, const Qt::KeyboardModifiers modifiers, int index = -1)
         : touchPoints(touchPoints)
         , eventTime(eventTime)
         , action(action)
         , eventId(++s_eventId)
         , flags(flagsFromModifiers(modifiers))
         , index(index)
-        , dpiScale(dpiScale)
     {
         // ACTION_DOWN and ACTION_UP must be accesssed through pointer_index 0
         Q_ASSERT((action != Action::DOWN && action != Action::UP) || index == 0);
@@ -206,8 +205,8 @@ public:
     int GetActionIndex() const override { return index; }
     size_t GetPointerCount() const override { return touchPoints.size(); }
     int GetPointerId(size_t pointer_index) const override { return touchPoints.at(pointer_index).id(); }
-    float GetX(size_t pointer_index) const override { return touchPoints.at(pointer_index).pos().x() / dpiScale; }
-    float GetY(size_t pointer_index) const override { return touchPoints.at(pointer_index).pos().y() / dpiScale; }
+    float GetX(size_t pointer_index) const override { return touchPoints.at(pointer_index).pos().x(); }
+    float GetY(size_t pointer_index) const override { return touchPoints.at(pointer_index).pos().y(); }
     float GetRawX(size_t pointer_index) const override { return touchPoints.at(pointer_index).screenPos().x(); }
     float GetRawY(size_t pointer_index) const override { return touchPoints.at(pointer_index).screenPos().y(); }
     float GetTouchMajor(size_t pointer_index) const override
@@ -247,7 +246,6 @@ private:
     const uint32_t eventId;
     int flags;
     int index;
-    float dpiScale;
 };
 
 RenderWidgetHostViewQt::RenderWidgetHostViewQt(content::RenderWidgetHost *widget)
@@ -434,9 +432,8 @@ bool RenderWidgetHostViewQt::IsShowing()
 gfx::Rect RenderWidgetHostViewQt::GetViewBounds() const
 {
     QRectF p = m_delegate->contentsRect();
-    float s = dpiScale();
-    gfx::Point p1(floor(p.x() / s), floor(p.y() / s));
-    gfx::Point p2(ceil(p.right() /s), ceil(p.bottom() / s));
+    gfx::Point p1(floor(p.x()), floor(p.y()));
+    gfx::Point p2(ceil(p.right()), ceil(p.bottom()));
     return gfx::BoundingRect(p1, p2);
 }
 
@@ -681,11 +678,6 @@ void RenderWidgetHostViewQt::SubmitCompositorFrame(const viz::LocalSurfaceId &lo
     if (frame_token)
         OnFrameTokenChangedForView(frame_token);
 
-    // Support experimental.viewport.devicePixelRatio, see GetScreenInfo implementation below.
-    float dpiScale = this->dpiScale();
-    if (dpiScale != 0 && dpiScale != 1)
-        frame.metadata.device_scale_factor /= dpiScale;
-
     m_compositor->submitFrame(
         std::move(frame),
         base::BindOnce(&RenderWidgetHostViewQtDelegate::update, base::Unretained(m_delegate.get())));
@@ -714,9 +706,6 @@ void RenderWidgetHostViewQt::GetScreenInfo(content::ScreenInfo *results) const
     if (!window)
         return;
     GetScreenInfoFromNativeWindow(window, results);
-
-    // Support experimental.viewport.devicePixelRatio
-    results->device_scale_factor *= dpiScale();
 }
 
 gfx::Rect RenderWidgetHostViewQt::GetBoundsInRootWindow()
@@ -1182,11 +1171,6 @@ QList<QTouchEvent::TouchPoint> RenderWidgetHostViewQt::mapTouchPointIds(const QL
     return outputPoints;
 }
 
-float RenderWidgetHostViewQt::dpiScale() const
-{
-    return m_adapterClient ? m_adapterClient->dpiScale() : 1.0;
-}
-
 bool RenderWidgetHostViewQt::IsPopup() const
 {
     return widget_type_ == content::WidgetType::kPopup;
@@ -1414,7 +1398,7 @@ void RenderWidgetHostViewQt::handleWheelEvent(QWheelEvent *ev)
 {
     if (!m_wheelAckPending) {
         Q_ASSERT(m_pendingWheelEvents.isEmpty());
-        blink::WebMouseWheelEvent webEvent = WebEventFactory::toWebWheelEvent(ev, dpiScale());
+        blink::WebMouseWheelEvent webEvent = WebEventFactory::toWebWheelEvent(ev);
         m_wheelAckPending = (webEvent.phase != blink::WebMouseWheelEvent::kPhaseEnded);
         m_mouseWheelPhaseHandler.AddPhaseIfNeededAndScheduleEndEvent(webEvent, false);
         host()->ForwardWheelEvent(webEvent);
@@ -1422,10 +1406,10 @@ void RenderWidgetHostViewQt::handleWheelEvent(QWheelEvent *ev)
     }
     if (!m_pendingWheelEvents.isEmpty()) {
         // Try to combine with this wheel event with the last pending one.
-        if (WebEventFactory::coalesceWebWheelEvent(m_pendingWheelEvents.last(), ev, dpiScale()))
+        if (WebEventFactory::coalesceWebWheelEvent(m_pendingWheelEvents.last(), ev))
             return;
     }
-    m_pendingWheelEvents.append(WebEventFactory::toWebWheelEvent(ev, dpiScale()));
+    m_pendingWheelEvents.append(WebEventFactory::toWebWheelEvent(ev));
 }
 
 void RenderWidgetHostViewQt::WheelEventAck(const blink::WebMouseWheelEvent &event, content::InputEventAckState /*ack_result*/)
@@ -1460,9 +1444,7 @@ void RenderWidgetHostViewQt::handleGestureEvent(QNativeGestureEvent *ev)
     const Qt::NativeGestureType type = ev->gestureType();
     // These are the only supported gestures by Chromium so far.
     if (type == Qt::ZoomNativeGesture || type == Qt::SmartZoomNativeGesture) {
-        host()->ForwardGestureEvent(WebEventFactory::toWebGestureEvent(
-                                        ev,
-                                        static_cast<double>(dpiScale())));
+        host()->ForwardGestureEvent(WebEventFactory::toWebGestureEvent(ev));
     }
 }
 #endif
@@ -1508,7 +1490,7 @@ void RenderWidgetHostViewQt::handleTouchEvent(QTouchEvent *ev)
             break;
         }
 
-        MotionEventQt motionEvent(touchPoints, eventTimestamp, action, ev->modifiers(), dpiScale(), 0);
+        MotionEventQt motionEvent(touchPoints, eventTimestamp, action, ev->modifiers(), 0);
         if (m_touchSelectionController->WillHandleTouchEvent(motionEvent)) {
             ev->accept();
             return;
@@ -1539,8 +1521,7 @@ void RenderWidgetHostViewQt::handleTouchEvent(QTouchEvent *ev)
         if (touchPoints.isEmpty())
             touchPoints = m_previousTouchPoints;
         clearPreviousTouchMotionState();
-        MotionEventQt cancelEvent(touchPoints, eventTimestamp, ui::MotionEvent::Action::CANCEL,
-                                  ev->modifiers(), dpiScale());
+        MotionEventQt cancelEvent(touchPoints, eventTimestamp, ui::MotionEvent::Action::CANCEL, ev->modifiers());
         processMotionEvent(cancelEvent);
         return;
     }
@@ -1593,8 +1574,7 @@ void RenderWidgetHostViewQt::handleTouchEvent(QTouchEvent *ev)
             continue;
         }
 
-        MotionEventQt motionEvent(touchPoints, eventTimestamp, action, ev->modifiers(), dpiScale(),
-                                  i);
+        MotionEventQt motionEvent(touchPoints, eventTimestamp, action, ev->modifiers(), i);
         processMotionEvent(motionEvent);
     }
 }
@@ -1611,7 +1591,7 @@ void RenderWidgetHostViewQt::handlePointerEvent(T *event)
 {
     // Currently WebMouseEvent is a subclass of WebPointerProperties, so basically
     // tablet events are mouse events with extra properties.
-    blink::WebMouseEvent webEvent = WebEventFactory::toWebMouseEvent(event, dpiScale());
+    blink::WebMouseEvent webEvent = WebEventFactory::toWebMouseEvent(event);
     if ((webEvent.GetType() == blink::WebInputEvent::kMouseDown || webEvent.GetType() == blink::WebInputEvent::kMouseUp)
             && webEvent.button == blink::WebMouseEvent::Button::kNoButton) {
         // Blink can only handle the 3 main mouse-buttons and may assert when processing mouse-down for no button.
@@ -1657,7 +1637,7 @@ void RenderWidgetHostViewQt::handlePointerEvent(T *event)
 
 void RenderWidgetHostViewQt::handleHoverEvent(QHoverEvent *ev)
 {
-    host()->ForwardMouseEvent(WebEventFactory::toWebMouseEvent(ev, dpiScale()));
+    host()->ForwardMouseEvent(WebEventFactory::toWebMouseEvent(ev));
 }
 
 void RenderWidgetHostViewQt::handleFocusEvent(QFocusEvent *ev)
diff --git a/src/core/render_widget_host_view_qt.h b/src/core/render_widget_host_view_qt.h
index b9efc996f..f7bd82f03 100644
--- a/src/core/render_widget_host_view_qt.h
+++ b/src/core/render_widget_host_view_qt.h
@@ -234,7 +234,6 @@ private:
     void processMotionEvent(const ui::MotionEvent &motionEvent);
     void clearPreviousTouchMotionState();
     QList<QTouchEvent::TouchPoint> mapTouchPointIds(const QList<QTouchEvent::TouchPoint> &inputPoints);
-    float dpiScale() const;
     void updateNeedsBeginFramesInternal();
 
     bool IsPopup() const;
diff --git a/src/core/renderer/content_renderer_client_qt.cpp b/src/core/renderer/content_renderer_client_qt.cpp
index 5aaf7ab7b..296e78b07 100644
--- a/src/core/renderer/content_renderer_client_qt.cpp
+++ b/src/core/renderer/content_renderer_client_qt.cpp
@@ -40,6 +40,8 @@
 #include "renderer/content_renderer_client_qt.h"
 
 #include "common/qt_messages.h"
+#include "extensions/buildflags/buildflags.h"
+#include "printing/buildflags/buildflags.h"
 #include "renderer/content_settings_observer_qt.h"
 #include "base/strings/string_split.h"
 #if QT_CONFIG(webengine_spellchecker)
@@ -85,6 +87,12 @@
 #if QT_CONFIG(webengine_webchannel)
 #include "renderer/web_channel_ipc_transport.h"
 #endif
+
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "common/extensions/extensions_client_qt.h"
+#include "extensions/extensions_renderer_client_qt.h"
+#endif //ENABLE_EXTENSIONS
+
 #include "services/service_manager/public/cpp/binder_registry.h"
 #include "services/service_manager/public/cpp/connector.h"
 
@@ -106,6 +114,10 @@ static const char kHttpErrorDomain[] = "http";
 
 ContentRendererClientQt::ContentRendererClientQt()
 {
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionsClient::Set(extensions::ExtensionsClientQt::GetInstance());
+    extensions::ExtensionsRendererClient::Set(ExtensionsRendererClientQt::GetInstance());
+#endif
 }
 
 ContentRendererClientQt::~ContentRendererClientQt()
@@ -139,6 +151,9 @@ void ContentRendererClientQt::RenderThreadStarted()
     blink::WebString file(blink::WebString::FromASCII("file"));
     blink::WebSecurityPolicy::AddOriginAccessAllowListEntry(qrc, file, blink::WebString(), true,
                                                             network::mojom::CORSOriginAccessMatchPriority::kDefaultPriority);
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    ExtensionsRendererClientQt::GetInstance()->RenderThreadStarted();
+#endif
 }
 
 void ContentRendererClientQt::RenderViewCreated(content::RenderView* render_view)
@@ -150,11 +165,12 @@ void ContentRendererClientQt::RenderViewCreated(content::RenderView* render_view
 
 void ContentRendererClientQt::RenderFrameCreated(content::RenderFrame* render_frame)
 {
-    new QtWebEngineCore::RenderFrameObserverQt(render_frame);
+    QtWebEngineCore::RenderFrameObserverQt *render_frame_observer = new QtWebEngineCore::RenderFrameObserverQt(render_frame);
 #if QT_CONFIG(webengine_webchannel)
     if (render_frame->IsMainFrame())
         new WebChannelIPCTransport(render_frame);
 #endif
+
     UserResourceController::instance()->renderFrameCreated(render_frame);
 
     new QtWebEngineCore::ContentSettingsObserverQt(render_frame);
@@ -167,17 +183,41 @@ void ContentRendererClientQt::RenderFrameCreated(content::RenderFrame* render_fr
                 render_frame,
                 base::WrapUnique(new PrintWebViewHelperDelegateQt()));
 #endif // QT_CONFIG(webengine_printing_and_pdf)
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    auto registry = std::make_unique<service_manager::BinderRegistry>();
+    ExtensionsRendererClientQt::GetInstance()->RenderFrameCreated(render_frame, render_frame_observer->registry());
+#endif
 }
 
-void ContentRendererClientQt::RunScriptsAtDocumentEnd(content::RenderFrame* render_frame)
+void ContentRendererClientQt::RunScriptsAtDocumentStart(content::RenderFrame *render_frame)
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    ExtensionsRendererClientQt::GetInstance()->RunScriptsAtDocumentStart(render_frame);
+    // |render_frame| might be dead by now.
+#endif
+}
+
+void ContentRendererClientQt::RunScriptsAtDocumentEnd(content::RenderFrame *render_frame)
 {
     // Check whether the render_frame has been created and has not been detached yet.
     // Otherwise the WebFrame is not available.
     RenderFrameObserverQt *render_frame_observer = RenderFrameObserverQt::Get(render_frame);
-    if (!render_frame_observer || render_frame_observer->isFrameDetached())
-        return; // The frame is invisible to scripts.
 
-    UserResourceController::instance()->RunScriptsAtDocumentEnd(render_frame);
+    if (render_frame_observer && !render_frame_observer->isFrameDetached())
+        UserResourceController::instance()->RunScriptsAtDocumentEnd(render_frame);
+
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    ExtensionsRendererClientQt::GetInstance()->RunScriptsAtDocumentEnd(render_frame);
+    // |render_frame| might be dead by now.
+#endif
+}
+
+void ContentRendererClientQt::RunScriptsAtDocumentIdle(content::RenderFrame *render_frame)
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    ExtensionsRendererClientQt::GetInstance()->RunScriptsAtDocumentIdle(render_frame);
+    // |render_frame| might be dead by now.
+#endif
 }
 
 bool ContentRendererClientQt::HasErrorPage(int httpStatusCode)
@@ -261,6 +301,29 @@ blink::WebPrescientNetworking *ContentRendererClientQt::GetPrescientNetworking()
     return m_prescientNetworkingDispatcher.get();
 }
 
+bool ContentRendererClientQt::OverrideCreatePlugin(
+    content::RenderFrame* render_frame,
+    const blink::WebPluginParams& params, blink::WebPlugin** plugin)
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    if (!ExtensionsRendererClientQt::GetInstance()->OverrideCreatePlugin(render_frame, params))
+        return false;
+#endif //ENABLE_EXTENSIONS
+    return content::ContentRendererClient::OverrideCreatePlugin(render_frame, params, plugin);
+}
+
+content::BrowserPluginDelegate* ContentRendererClientQt::CreateBrowserPluginDelegate(content::RenderFrame *render_frame,
+                                                                                     const content::WebPluginInfo &info,
+                                                                                     const std::string &mime_type,
+                                                                                     const GURL &original_url)
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    return ExtensionsRendererClientQt::GetInstance()->CreateBrowserPluginDelegate(render_frame, info, mime_type, original_url);
+#else
+    return nullptr;
+#endif
+}
+
 void ContentRendererClientQt::OnStart()
 {
     context()->connector()->BindConnectorRequest(std::move(m_connectorRequest));
@@ -489,6 +552,21 @@ void ContentRendererClientQt::InitSpellCheck()
 }
 #endif
 
+void ContentRendererClientQt::WillSendRequest(blink::WebLocalFrame *frame,
+                                              ui::PageTransition transition_type,
+                                              const blink::WebURL &url,
+                                              const url::Origin *initiator_origin,
+                                              GURL *new_url,
+                                              bool *attach_same_site_cookies)
+{
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    ExtensionsRendererClientQt::GetInstance()->WillSendRequest(frame, transition_type, url, initiator_origin, new_url, attach_same_site_cookies);
+    if (!new_url->is_empty())
+        return;
+#endif
+    content::ContentRendererClient::WillSendRequest(frame, transition_type, url, initiator_origin, new_url, attach_same_site_cookies);
+}
+
 void ContentRendererClientQt::CreateRendererService(service_manager::mojom::ServiceRequest service_request)
 {
     m_serviceContext = std::make_unique<service_manager::ServiceContext>(
diff --git a/src/core/renderer/content_renderer_client_qt.h b/src/core/renderer/content_renderer_client_qt.h
index 2a353caa6..8955a3797 100644
--- a/src/core/renderer/content_renderer_client_qt.h
+++ b/src/core/renderer/content_renderer_client_qt.h
@@ -96,7 +96,20 @@ public:
     blink::WebPrescientNetworking* GetPrescientNetworking() override;
     void AddSupportedKeySystems(std::vector<std::unique_ptr<media::KeySystemProperties>>* key_systems) override;
 
-    void RunScriptsAtDocumentEnd(content::RenderFrame* render_frame) override;
+    void RunScriptsAtDocumentStart(content::RenderFrame *render_frame) override;
+    void RunScriptsAtDocumentEnd(content::RenderFrame *render_frame) override;
+    void RunScriptsAtDocumentIdle(content::RenderFrame *render_frame) override;
+    bool OverrideCreatePlugin(content::RenderFrame* render_frame,
+        const blink::WebPluginParams& params, blink::WebPlugin** plugin) override;
+    content::BrowserPluginDelegate* CreateBrowserPluginDelegate(content::RenderFrame* render_frame,
+        const content::WebPluginInfo& info, const std::string& mime_type, const GURL& original_url) override;
+
+    void WillSendRequest(blink::WebLocalFrame *frame,
+                         ui::PageTransition transition_type,
+                         const blink::WebURL &url,
+                         const url::Origin *initiator_origin,
+                         GURL *new_url,
+                         bool *attach_same_site_cookies) override;
 
     void CreateRendererService(service_manager::mojom::ServiceRequest service_request) override;
 
diff --git a/src/core/renderer/extensions/extensions_dispatcher_delegate_qt.cpp b/src/core/renderer/extensions/extensions_dispatcher_delegate_qt.cpp
new file mode 100644
index 000000000..418429330
--- /dev/null
+++ b/src/core/renderer/extensions/extensions_dispatcher_delegate_qt.cpp
@@ -0,0 +1,52 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "extensions_dispatcher_delegate_qt.h"
+
+namespace QtWebEngineCore {
+
+ExtensionsDispatcherDelegateQt::ExtensionsDispatcherDelegateQt()
+{
+}
+
+ExtensionsDispatcherDelegateQt::~ExtensionsDispatcherDelegateQt()
+{
+}
+
+} //namespace QtWebEngineCore
diff --git a/src/core/renderer/extensions/extensions_dispatcher_delegate_qt.h b/src/core/renderer/extensions/extensions_dispatcher_delegate_qt.h
new file mode 100644
index 000000000..25aa18e71
--- /dev/null
+++ b/src/core/renderer/extensions/extensions_dispatcher_delegate_qt.h
@@ -0,0 +1,60 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef EXTENSIONSDISPATCHERDELEGATEQT_H
+#define EXTENSIONSDISPATCHERDELEGATEQT_H
+
+#include "base/macros.h"
+#include "extensions/renderer/dispatcher_delegate.h"
+
+namespace QtWebEngineCore {
+
+class ExtensionsDispatcherDelegateQt : public extensions::DispatcherDelegate
+{
+public:
+    ExtensionsDispatcherDelegateQt();
+    ~ExtensionsDispatcherDelegateQt() override;
+
+private:
+    DISALLOW_COPY_AND_ASSIGN(ExtensionsDispatcherDelegateQt);
+};
+
+} // namespace QtWebEngineCore
+
+#endif // EXTENSIONSDISPATCHERDELEGATEQT_H
diff --git a/src/core/renderer/extensions/extensions_renderer_client_qt.cpp b/src/core/renderer/extensions/extensions_renderer_client_qt.cpp
new file mode 100644
index 000000000..c41d9e6a4
--- /dev/null
+++ b/src/core/renderer/extensions/extensions_renderer_client_qt.cpp
@@ -0,0 +1,203 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// based on chrome/renderer/extensions/chrome_extensions_renderer_client.cc:
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "extensions_renderer_client_qt.h"
+
+#include "extensions_dispatcher_delegate_qt.h"
+#include "renderer_permissions_policy_delegate_qt.h"
+#include "resource_request_policy_qt.h"
+
+#include "base/command_line.h"
+#include "base/lazy_instance.h"
+#include "content/public/common/content_constants.h"
+#include "content/public/common/content_switches.h"
+#include "content/public/renderer/render_frame.h"
+#include "content/public/renderer/render_thread.h"
+#include "extensions/common/constants.h"
+#include "extensions/common/switches.h"
+#include "extensions/renderer/dispatcher.h"
+#include "extensions/renderer/extension_frame_helper.h"
+#include "extensions/renderer/extensions_render_frame_observer.h"
+#include "extensions/renderer/guest_view/extensions_guest_view_container.h"
+#include "extensions/renderer/guest_view/extensions_guest_view_container_dispatcher.h"
+#include "extensions/renderer/guest_view/mime_handler_view/mime_handler_view_container.h"
+#include "extensions/renderer/renderer_extension_registry.h"
+#include "extensions/renderer/script_context.h"
+#include "third_party/blink/public/platform/web_url.h"
+#include "third_party/blink/public/web/web_plugin_params.h"
+
+namespace chrome {
+const char kExtensionInvalidRequestURL[] = "chrome-extension://invalid/";
+const char kExtensionResourceInvalidRequestURL[] = "chrome-extension-resource://invalid/";
+}
+
+namespace QtWebEngineCore {
+
+ExtensionsRendererClientQt::ExtensionsRendererClientQt()
+{
+}
+
+ExtensionsRendererClientQt::~ExtensionsRendererClientQt()
+{
+}
+
+// Returns true if the current render process was launched incognito.
+bool ExtensionsRendererClientQt::IsIncognitoProcess() const
+{
+    return false;
+}
+
+// Returns the lowest isolated world ID available to extensions.
+// Must be greater than 0. See blink::WebFrame::executeScriptInIsolatedWorld
+// (third_party/WebKit/public/web/WebFrame.h) for additional context.
+int ExtensionsRendererClientQt::GetLowestIsolatedWorldId() const
+{
+    return 257;
+}
+
+// static
+ExtensionsRendererClientQt *ExtensionsRendererClientQt::GetInstance()
+{
+    static base::LazyInstance<ExtensionsRendererClientQt>::Leaky client =
+            LAZY_INSTANCE_INITIALIZER;
+    return client.Pointer();
+}
+
+extensions::Dispatcher *ExtensionsRendererClientQt::GetDispatcher()
+{
+    return extension_dispatcher_.get();
+}
+
+void ExtensionsRendererClientQt::OnExtensionLoaded(const extensions::Extension &extension)
+{
+    resource_request_policy_->OnExtensionLoaded(extension);
+}
+
+void ExtensionsRendererClientQt::OnExtensionUnloaded(const extensions::ExtensionId &extension_id)
+{
+    resource_request_policy_->OnExtensionUnloaded(extension_id);
+}
+
+void ExtensionsRendererClientQt::RenderThreadStarted()
+{
+    content::RenderThread *thread = content::RenderThread::Get();
+    // ChromeRenderViewTest::SetUp() creates its own ExtensionDispatcher and
+    // injects it using SetExtensionDispatcher(). Don't overwrite it.
+    if (!extension_dispatcher_)
+        extension_dispatcher_.reset(new extensions::Dispatcher(std::make_unique<ExtensionsDispatcherDelegateQt>()));
+    permissions_policy_delegate_.reset(new RendererPermissionsPolicyDelegateQt(extension_dispatcher_.get()));
+    resource_request_policy_.reset(new extensions::ResourceRequestPolicyQt(extension_dispatcher_.get()));
+    guest_view_container_dispatcher_.reset(new extensions::ExtensionsGuestViewContainerDispatcher());
+
+    thread->AddObserver(extension_dispatcher_.get());
+    thread->AddObserver(guest_view_container_dispatcher_.get());
+}
+
+void ExtensionsRendererClientQt::RenderFrameCreated(content::RenderFrame *render_frame,
+                                                    service_manager::BinderRegistry *registry)
+{
+    new extensions::ExtensionsRenderFrameObserver(render_frame, registry);
+    new extensions::ExtensionFrameHelper(render_frame,
+                                         extension_dispatcher_.get());
+    extension_dispatcher_->OnRenderFrameCreated(render_frame);
+}
+
+bool ExtensionsRendererClientQt::OverrideCreatePlugin(content::RenderFrame *render_frame,
+                                                      const blink::WebPluginParams &params)
+{
+    if (params.mime_type.Utf8() != content::kBrowserPluginMimeType)
+        return true;
+    bool guest_view_api_available = false;
+    return !guest_view_api_available;
+}
+
+void ExtensionsRendererClientQt::WillSendRequest(blink::WebLocalFrame *frame,
+                                                 ui::PageTransition transition_type,
+                                                 const blink::WebURL &url,
+                                                 const url::Origin *initiator_origin,
+                                                 GURL *new_url,
+                                                 bool *attach_same_site_cookies)
+{
+    if (url.ProtocolIs(extensions::kExtensionScheme) &&
+            !resource_request_policy_->CanRequestResource(url, frame, transition_type)) {
+        *new_url = GURL(chrome::kExtensionInvalidRequestURL);
+    }
+}
+
+bool ExtensionsRendererClientQt::ShouldFork(blink::WebLocalFrame *frame,
+                                            const GURL &url,
+                                            bool is_initial_navigation,
+                                            bool is_server_redirect,
+                                            bool *send_referrer)
+{
+    return false; // TODO: Fix this to a sensible value
+}
+
+content::BrowserPluginDelegate *ExtensionsRendererClientQt::CreateBrowserPluginDelegate(content::RenderFrame *render_frame,
+                                                                                        const content::WebPluginInfo &info,
+                                                                                        const std::string &mime_type,
+                                                                                        const GURL &original_url)
+{
+    if (mime_type == content::kBrowserPluginMimeType)
+        return new extensions::ExtensionsGuestViewContainer(render_frame);
+    return new extensions::MimeHandlerViewContainer(render_frame, info, mime_type, original_url);
+}
+
+void ExtensionsRendererClientQt::RunScriptsAtDocumentStart(content::RenderFrame *render_frame)
+{
+    extension_dispatcher_->RunScriptsAtDocumentStart(render_frame);
+}
+
+void ExtensionsRendererClientQt::RunScriptsAtDocumentEnd(content::RenderFrame *render_frame)
+{
+    extension_dispatcher_->RunScriptsAtDocumentEnd(render_frame);
+}
+
+void ExtensionsRendererClientQt::RunScriptsAtDocumentIdle(content::RenderFrame *render_frame)
+{
+    extension_dispatcher_->RunScriptsAtDocumentIdle(render_frame);
+}
+
+
+} // namespace QtWebEngineCore
diff --git a/src/core/renderer/extensions/extensions_renderer_client_qt.h b/src/core/renderer/extensions/extensions_renderer_client_qt.h
new file mode 100644
index 000000000..2d45d255a
--- /dev/null
+++ b/src/core/renderer/extensions/extensions_renderer_client_qt.h
@@ -0,0 +1,135 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef EXTENSIONSRENDERERCLIENTQT_H
+#define EXTENSIONSRENDERERCLIENTQT_H
+
+#include <memory>
+#include <string>
+
+#include "base/macros.h"
+#include "extensions/renderer/extensions_renderer_client.h"
+#include "services/service_manager/public/cpp/binder_registry.h"
+#include "ui/base/page_transition_types.h"
+
+class GURL;
+
+namespace blink {
+class WebLocalFrame;
+struct WebPluginParams;
+class WebURL;
+}
+
+namespace content {
+class BrowserPluginDelegate;
+class RenderFrame;
+class RenderView;
+struct WebPluginInfo;
+}
+
+namespace url {
+class Origin;
+}
+
+namespace extensions {
+class Dispatcher;
+class ExtensionsGuestViewContainerDispatcher;
+class ResourceRequestPolicyQt;
+}
+
+namespace QtWebEngineCore {
+
+class ExtensionsDispatcherDelegateQt;
+class RendererPermissionsPolicyDelegateQt;
+
+class ExtensionsRendererClientQt : public extensions::ExtensionsRendererClient
+{
+public:
+    ExtensionsRendererClientQt();
+    ~ExtensionsRendererClientQt() override;
+
+    // extensions::ExtensionsRendererClient implementation.
+    bool IsIncognitoProcess() const override;
+    int GetLowestIsolatedWorldId() const override;
+    extensions::Dispatcher *GetDispatcher() override;
+    void OnExtensionLoaded(const extensions::Extension &extension) override;
+    void OnExtensionUnloaded(const extensions::ExtensionId &extension_id) override;
+
+    // Match ContentRendererClientQt's method names...
+    void RenderThreadStarted();
+    void RenderFrameCreated(content::RenderFrame *, service_manager::BinderRegistry *);
+    bool OverrideCreatePlugin(content::RenderFrame *render_frame,
+                              const blink::WebPluginParams &params);
+    void WillSendRequest(blink::WebLocalFrame *frame,
+                         ui::PageTransition transition_type,
+                         const blink::WebURL &url,
+                         const url::Origin *initiator_origin,
+                         GURL *new_url,
+                         bool *attach_same_site_cookies);
+
+    static bool ShouldFork(blink::WebLocalFrame *frame,
+                           const GURL &url,
+                           bool is_initial_navigation,
+                           bool is_server_redirect,
+                           bool *send_referrer);
+    static content::BrowserPluginDelegate *CreateBrowserPluginDelegate(content::RenderFrame *render_frame,
+                                                                       const content::WebPluginInfo &info,
+                                                                       const std::string &mime_type,
+                                                                       const GURL &original_url);
+
+    void RunScriptsAtDocumentStart(content::RenderFrame *render_frame);
+    void RunScriptsAtDocumentEnd(content::RenderFrame *render_frame);
+    void RunScriptsAtDocumentIdle(content::RenderFrame *render_frame);
+
+    extensions::Dispatcher *extension_dispatcher()
+    { return extension_dispatcher_.get(); }
+
+    static ExtensionsRendererClientQt *GetInstance();
+
+private:
+    std::unique_ptr<ExtensionsDispatcherDelegateQt> extension_dispatcher_delegate_;
+    std::unique_ptr<RendererPermissionsPolicyDelegateQt> permissions_policy_delegate_;
+    std::unique_ptr<extensions::Dispatcher> extension_dispatcher_;
+    std::unique_ptr<extensions::ExtensionsGuestViewContainerDispatcher> guest_view_container_dispatcher_;
+    std::unique_ptr<extensions::ResourceRequestPolicyQt> resource_request_policy_;
+};
+
+} // namespace QtWebEngineCore
+
+#endif // EXTENSIONSRENDERERCLIENTQT_H
diff --git a/src/core/renderer/extensions/renderer_permissions_policy_delegate_qt.cpp b/src/core/renderer/extensions/renderer_permissions_policy_delegate_qt.cpp
new file mode 100644
index 000000000..39412b76c
--- /dev/null
+++ b/src/core/renderer/extensions/renderer_permissions_policy_delegate_qt.cpp
@@ -0,0 +1,66 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "renderer_permissions_policy_delegate_qt.h"
+
+#include "extensions/common/constants.h"
+#include "extensions/common/extensions_client.h"
+#include "extensions/common/manifest_constants.h"
+#include "extensions/common/switches.h"
+#include "extensions/renderer/dispatcher.h"
+
+namespace QtWebEngineCore {
+
+RendererPermissionsPolicyDelegateQt::RendererPermissionsPolicyDelegateQt(extensions::Dispatcher *dispatcher)
+        : m_dispatcher(dispatcher)
+{
+    extensions::PermissionsData::SetPolicyDelegate(this);
+}
+
+RendererPermissionsPolicyDelegateQt::~RendererPermissionsPolicyDelegateQt()
+{
+    extensions::PermissionsData::SetPolicyDelegate(nullptr);
+}
+
+bool RendererPermissionsPolicyDelegateQt::IsRestrictedUrl(const GURL &, std::string *)
+{
+    return false;
+}
+
+} // namespace QtWebEngineCore
diff --git a/src/core/renderer/extensions/renderer_permissions_policy_delegate_qt.h b/src/core/renderer/extensions/renderer_permissions_policy_delegate_qt.h
new file mode 100644
index 000000000..e2af47657
--- /dev/null
+++ b/src/core/renderer/extensions/renderer_permissions_policy_delegate_qt.h
@@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef RENDERERPERMISSIONSPOLICYDELEGATEQT_H
+#define RENDERERPERMISSIONSPOLICYDELEGATEQT_H
+
+#include "base/macros.h"
+#include "extensions/common/permissions/permissions_data.h"
+
+namespace extensions {
+class Dispatcher;
+}
+
+namespace QtWebEngineCore {
+
+class RendererPermissionsPolicyDelegateQt : public extensions::PermissionsData::PolicyDelegate
+{
+public:
+    explicit RendererPermissionsPolicyDelegateQt(extensions::Dispatcher *dispatcher);
+    ~RendererPermissionsPolicyDelegateQt() override;
+
+    bool IsRestrictedUrl(const GURL &, std::string *) override;
+
+private:
+    extensions::Dispatcher *m_dispatcher;
+
+    DISALLOW_COPY_AND_ASSIGN(RendererPermissionsPolicyDelegateQt);
+};
+
+} // namespace QtWebEngineCore
+
+#endif // RENDERERPERMISSIONSPOLICYDELEGATEQT_H
diff --git a/src/core/renderer/extensions/resource_request_policy_qt.cpp b/src/core/renderer/extensions/resource_request_policy_qt.cpp
new file mode 100644
index 000000000..dc5a90120
--- /dev/null
+++ b/src/core/renderer/extensions/resource_request_policy_qt.cpp
@@ -0,0 +1,182 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// based on chrome/renderer/extensions/resource_request_policy.cc:
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "resource_request_policy_qt.h"
+
+#include "base/strings/stringprintf.h"
+#include "chrome/common/url_constants.h"
+#include "extensions/common/constants.h"
+#include "extensions/common/manifest_handlers/web_accessible_resources_info.h"
+#include "extensions/common/manifest_handlers/webview_info.h"
+#include "extensions/renderer/dispatcher.h"
+#include "third_party/blink/public/web/web_console_message.h"
+#include "third_party/blink/public/web/web_document.h"
+#include "third_party/blink/public/web/web_local_frame.h"
+
+namespace extensions {
+ResourceRequestPolicyQt::ResourceRequestPolicyQt(Dispatcher *dispatcher)
+        : m_dispatcher(dispatcher)
+{
+}
+
+void ResourceRequestPolicyQt::OnExtensionLoaded(const Extension &extension)
+{
+    if (WebAccessibleResourcesInfo::HasWebAccessibleResources(&extension)
+        || WebviewInfo::HasWebviewAccessibleResources(extension, m_dispatcher->webview_partition_id())
+//          // Hosted app icons are accessible.
+//          // TODO(devlin): Should we incorporate this into
+//          // WebAccessibleResourcesInfo?
+//        || (extension.is_hosted_app() && !IconsInfo::GetIcons(&extension).empty())
+       ) {
+        m_web_accessible_ids.insert(extension.id());
+    }
+}
+
+void ResourceRequestPolicyQt::OnExtensionUnloaded(const ExtensionId &extension_id)
+{
+    m_web_accessible_ids.erase(extension_id);
+}
+
+// Returns true if the chrome-extension:// |resource_url| can be requested
+// from |frame_url|. In some cases this decision is made based upon how
+// this request was generated. Web triggered transitions are more restrictive
+// than those triggered through UI.
+bool ResourceRequestPolicyQt::CanRequestResource(const GURL &resource_url,
+                                                 blink::WebLocalFrame *frame,
+                                                 ui::PageTransition transition_type)
+{
+    CHECK(resource_url.SchemeIs(kExtensionScheme));
+
+    GURL frame_url = frame->GetDocument().Url();
+
+    // The page_origin may be GURL("null") for unique origins like data URLs,
+    // but this is ok for the checks below.  We only care if it matches the
+    // current extension or has a devtools scheme.
+    GURL page_origin = url::Origin(frame->Top()->GetSecurityOrigin()).GetURL();
+
+    GURL extension_origin = resource_url.GetOrigin();
+
+    // We always allow loads in the following cases, regardless of web accessible
+    // resources:
+
+    // Empty urls (needed for some edge cases when we have empty urls).
+    if (frame_url.is_empty())
+        return true;
+
+    // Extensions requesting their own resources (frame_url check is for images,
+    // page_url check is for iframes).
+    // TODO(devlin): We should be checking the ancestor chain, not just the
+    // top-level frame. Additionally, we should be checking the security origin
+    // of the frame, to account for about:blank subframes being scripted by an
+    // extension parent (though we'll still need the frame origin check for
+    // sandboxed frames).
+    if (frame_url.GetOrigin() == extension_origin || page_origin == extension_origin)
+        return true;
+
+    if (!ui::PageTransitionIsWebTriggerable(transition_type))
+        return true;
+
+    // Unreachable web page error page (to allow showing the icon of the
+    // unreachable app on this page).
+    if (frame_url == content::kUnreachableWebDataURL)
+        return true;
+
+    bool is_dev_tools = page_origin.SchemeIs(content::kChromeDevToolsScheme);
+    // Note: we check |web_accessible_ids_| (rather than first looking up the
+    // extension in the registry and checking that) to be more resistant against
+    // timing attacks. This way, determining access for an extension that isn't
+    // installed takes the same amount of time as determining access for an
+    // extension with no web accessible resources. We aren't worried about any
+    // extensions with web accessible resources, since those are inherently
+    // identifiable.
+    if (!is_dev_tools && !m_web_accessible_ids.count(extension_origin.host()))
+        return false;
+
+    const Extension* extension = RendererExtensionRegistry::Get()->GetExtensionOrAppByURL(resource_url);
+    if (is_dev_tools) {
+        // Allow the load in the case of a non-existent extension. We'll just get a
+        // 404 from the browser process.
+        // TODO(devlin): Can this happen? Does devtools potentially make requests
+        // to non-existent extensions?
+        if (!extension)
+            return true;
+//        // Devtools (chrome-extension:// URLs are loaded into frames of devtools to
+//        // support the devtools extension APIs).
+//        if (!chrome_manifest_urls::GetDevToolsPage(extension).is_empty())
+//            return true;
+    }
+
+    DCHECK(extension);
+
+    // Disallow loading of packaged resources for hosted apps. We don't allow
+    // hybrid hosted/packaged apps. The one exception is access to icons, since
+    // some extensions want to be able to do things like create their own
+    // launchers.
+    base::StringPiece resource_root_relative_path =
+            resource_url.path_piece().empty() ? base::StringPiece()
+                                              : resource_url.path_piece().substr(1);
+    if (extension->is_hosted_app() /*&& !IconsInfo::GetIcons(extension).ContainsPath(resource_root_relative_path)*/) {
+        LOG(ERROR) << "Denying load of " << resource_url.spec() << " from "
+                   << "hosted app.";
+        return false;
+    }
+
+    // Disallow loading of extension resources which are not explicitly listed
+    // as web or WebView accessible if the manifest version is 2 or greater.
+    if (!WebAccessibleResourcesInfo::IsResourceWebAccessible(extension, resource_url.path()) &&
+        !WebviewInfo::IsResourceWebviewAccessible(extension, m_dispatcher->webview_partition_id(), resource_url.path()))
+    {
+        std::string message = base::StringPrintf(
+                    "Denying load of %s. Resources must be listed in the "
+                    "web_accessible_resources manifest key in order to be loaded by "
+                    "pages outside the extension.",
+                    resource_url.spec().c_str());
+        frame->AddMessageToConsole(blink::WebConsoleMessage(blink::WebConsoleMessage::kLevelError, blink::WebString::FromUTF8(message)));
+        return false;
+    }
+
+    return true;
+}
+
+} // namespace extensions
diff --git a/src/core/renderer/extensions/resource_request_policy_qt.h b/src/core/renderer/extensions/resource_request_policy_qt.h
new file mode 100644
index 000000000..e6d4e79bb
--- /dev/null
+++ b/src/core/renderer/extensions/resource_request_policy_qt.h
@@ -0,0 +1,89 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef RESOURCEREQUESTPOLICYQT_H
+#define RESOURCEREQUESTPOLICYQT_H
+
+#include <set>
+
+#include "base/macros.h"
+#include "extensions/common/extension_id.h"
+#include "ui/base/page_transition_types.h"
+
+class GURL;
+
+namespace blink {
+class WebLocalFrame;
+}
+
+namespace extensions {
+
+class Dispatcher;
+class Extension;
+
+// Encapsulates the policy for when chrome-extension:// and
+// chrome-extension-resource:// URLs can be requested.
+class ResourceRequestPolicyQt
+{
+public:
+    explicit ResourceRequestPolicyQt(Dispatcher *dispatcher);
+
+    void OnExtensionLoaded(const Extension &extension);
+    void OnExtensionUnloaded(const ExtensionId &extension);
+
+    // Returns true if the chrome-extension:// |resource_url| can be requested
+    // from |frame_url|. In some cases this decision is made based upon how
+    // this request was generated. Web triggered transitions are more restrictive
+    // than those triggered through UI.
+    bool CanRequestResource(const GURL &resource_url,
+                            blink::WebLocalFrame *frame,
+                            ui::PageTransition transition_type);
+
+private:
+    Dispatcher *m_dispatcher;
+
+    // The set of extension IDs with any potentially web- or webview-accessible
+    // resources.
+    std::set<ExtensionId> m_web_accessible_ids;
+
+    DISALLOW_COPY_AND_ASSIGN(ResourceRequestPolicyQt);
+};
+} // namespace extensions
+
+#endif // RESOURCEREQUESTPOLICYQT_H
diff --git a/src/core/renderer/pepper/pepper_renderer_host_factory_qt.cpp b/src/core/renderer/pepper/pepper_renderer_host_factory_qt.cpp
index 4acf69043..33c744f13 100644
--- a/src/core/renderer/pepper/pepper_renderer_host_factory_qt.cpp
+++ b/src/core/renderer/pepper/pepper_renderer_host_factory_qt.cpp
@@ -44,9 +44,13 @@
 
 #include "pepper_renderer_host_factory_qt.h"
 #include "pepper_flash_renderer_host_qt.h"
+#include "qtwebenginecoreglobal_p.h"
 
 #include "base/memory/ptr_util.h"
 #include "chrome/renderer/pepper/pepper_flash_font_file_host.h"
+#if QT_CONFIG(webengine_printing_and_pdf)
+#include "components/pdf/renderer/pepper_pdf_host.h"
+#endif // QT_CONFIG(webengine_printing_and_pdf)
 #include "content/public/renderer/renderer_ppapi_host.h"
 #include "ppapi/host/ppapi_host.h"
 #include "ppapi/host/resource_host.h"
@@ -100,7 +104,7 @@ std::unique_ptr<ppapi::host::ResourceHost> PepperRendererHostFactoryQt::CreateRe
     // We should either rename PPB_FlashFont_File to PPB_FontFile_Private or get
     // rid of its use in PDF if possible.
     if (host_->GetPpapiHost()->permissions().HasPermission(ppapi::PERMISSION_FLASH)
-        || host_->GetPpapiHost()->permissions().HasPermission(ppapi::PERMISSION_PRIVATE)) {
+        || host_->GetPpapiHost()->permissions().HasPermission(ppapi::PERMISSION_PDF)) {
         switch (message.type()) {
         case PpapiHostMsg_FlashFontFile_Create::ID: {
             ppapi::proxy::SerializedFontDescription description;
@@ -115,14 +119,14 @@ std::unique_ptr<ppapi::host::ResourceHost> PepperRendererHostFactoryQt::CreateRe
         }
     }
 
-    if (host_->GetPpapiHost()->permissions().HasPermission(ppapi::PERMISSION_PRIVATE)) {
+#if QT_CONFIG(webengine_printing_and_pdf)
+    if (host_->GetPpapiHost()->permissions().HasPermission(ppapi::PERMISSION_PDF)) {
         switch (message.type()) {
         case PpapiHostMsg_PDF_Create::ID:
-            // Not implemented
-            break;
+            return std::make_unique<pdf::PepperPDFHost>(host_, instance, resource);
         }
     }
-
+#endif // QT_CONFIG(webengine_printing_and_pdf)
     return nullptr;
 }
 
diff --git a/src/core/renderer/print_web_view_helper_delegate_qt.cpp b/src/core/renderer/print_web_view_helper_delegate_qt.cpp
index e693cf096..67cdd6b66 100644
--- a/src/core/renderer/print_web_view_helper_delegate_qt.cpp
+++ b/src/core/renderer/print_web_view_helper_delegate_qt.cpp
@@ -41,8 +41,14 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE.Chromium file.
 
-#include "print_web_view_helper_delegate_qt.h"
+#include "content/public/renderer/render_frame.h"
+#include "content/public/renderer/render_view.h"
+#include "extensions/common/constants.h"
+#include "third_party/blink/public/web/web_document.h"
 #include "third_party/blink/public/web/web_element.h"
+#include "third_party/blink/public/web/web_local_frame.h"
+
+#include "print_web_view_helper_delegate_qt.h"
 #include "web_engine_library_info.h"
 
 namespace QtWebEngineCore {
@@ -58,6 +64,15 @@ bool PrintWebViewHelperDelegateQt::CancelPrerender(content::RenderFrame *)
 
 blink::WebElement PrintWebViewHelperDelegateQt::GetPdfElement(blink::WebLocalFrame* frame)
 {
+    GURL url = frame->GetDocument().Url();
+    if (url.SchemeIs(extensions::kExtensionScheme) && url.host() == extension_misc::kPdfExtensionId)
+    {
+        // <object> with id="plugin" is created in
+        // chrome/browser/resources/pdf/pdf.js.
+        auto plugin_element = frame->GetDocument().GetElementById("plugin");
+        CHECK(!plugin_element.IsNull());
+        return plugin_element;
+    }
     return blink::WebElement();
 }
 
diff --git a/src/core/renderer/render_frame_observer_qt.h b/src/core/renderer/render_frame_observer_qt.h
index bca45bd8e..4c05422bb 100644
--- a/src/core/renderer/render_frame_observer_qt.h
+++ b/src/core/renderer/render_frame_observer_qt.h
@@ -44,6 +44,8 @@
 #include "base/compiler_specific.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "content/public/renderer/render_frame_observer_tracker.h"
+#include "ppapi/buildflags/buildflags.h"
+#include "services/service_manager/public/cpp/binder_registry.h"
 
 namespace content {
 class RenderFrame;
@@ -67,10 +69,13 @@ public:
 
     bool isFrameDetached() const;
 
+    service_manager::BinderRegistry* registry() { return &registry_; }
+
 private:
     DISALLOW_COPY_AND_ASSIGN(RenderFrameObserverQt);
 
     bool m_isFrameDetached;
+    service_manager::BinderRegistry registry_;
 };
 
 } // namespace QtWebEngineCore
diff --git a/src/core/renderer_host/resource_dispatcher_host_delegate_qt.cpp b/src/core/renderer_host/resource_dispatcher_host_delegate_qt.cpp
new file mode 100644
index 000000000..0583060c6
--- /dev/null
+++ b/src/core/renderer_host/resource_dispatcher_host_delegate_qt.cpp
@@ -0,0 +1,166 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE.Chromium file.
+
+#include "resource_dispatcher_host_delegate_qt.h"
+
+#include "base/bind.h"
+#include "base/guid.h"
+#include "base/strings/stringprintf.h"
+#include "base/task/post_task.h"
+#include "content/public/browser/browser_task_traits.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/navigation_controller.h"
+
+#include "content/public/browser/render_frame_host.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/resource_dispatcher_host.h"
+#include "content/public/browser/resource_request_info.h"
+#include "content/public/browser/stream_info.h"
+#include "content/public/browser/web_contents.h"
+
+#include "extensions/extension_system_qt.h"
+#include "extensions/browser/info_map.h"
+#include "extensions/common/constants.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/manifest_handlers/mime_types_handler.h"
+
+#include "net/base/escape.h"
+#include "net/url_request/url_request.h"
+
+#include "resource_context_qt.h"
+#include "type_conversion.h"
+
+namespace QtWebEngineCore {
+
+void OnPdfStreamIntercepted(
+    const GURL& original_url,
+    std::string extension_id,
+    int frame_tree_node_id,
+    const content::ResourceRequestInfo::WebContentsGetter&
+        web_contents_getter) {
+    content::WebContents* web_contents = web_contents_getter.Run();
+    if (!web_contents)
+        return;
+
+    // The URL passes the original pdf resource url, that will be requested
+    // by the pdf viewer extension page.
+    content::NavigationController::LoadURLParams params(
+              GURL(base::StringPrintf("%s://%s/index.html?%s", extensions::kExtensionScheme,
+                   extension_id.c_str(),
+                   net::EscapeUrlEncodedData(original_url.spec(), false).c_str())));
+
+    params.frame_tree_node_id = frame_tree_node_id;
+    web_contents->GetController().LoadURLWithParams(params);
+}
+
+bool ResourceDispatcherHostDelegateQt::ShouldInterceptResourceAsStream(net::URLRequest *request,
+                                                                       const std::string &mime_type,
+                                                                       GURL *origin,
+                                                                       std::string *payload)
+{
+    const content::ResourceRequestInfo* info =
+        content::ResourceRequestInfo::ForRequest(request);
+
+    int render_process_host_id = -1;
+    int render_frame_id = -1;
+    if (!content::ResourceRequestInfo::GetRenderFrameForRequest(request, &render_process_host_id, &render_frame_id)) {
+      return false;
+    }
+
+    ResourceContextQt *context = static_cast<ResourceContextQt *>(info->GetContext());
+    std::vector<std::string> whitelist = MimeTypesHandler::GetMIMETypeWhitelist();
+
+    extensions::ExtensionSystemQt *extensionSystem = context->GetExtensionSystem();
+    if (!extensionSystem)
+        return false;
+
+    const scoped_refptr<const extensions::InfoMap> extension_info_map(extensionSystem->info_map());
+
+    for (const std::string &extension_id : whitelist) {
+        const extensions::Extension *extension = extension_info_map->extensions().GetByID(extension_id);
+        if (!extension)
+            continue;
+
+        MimeTypesHandler* handler = MimeTypesHandler::GetHandler(extension);
+        if (!handler)
+            continue;
+        if (handler->CanHandleMIMEType(mime_type)) {
+            StreamTargetInfo target_info;
+            *origin = extensions::Extension::GetBaseURLFromExtensionId(extension_id);
+            target_info.extension_id = extension_id;
+            target_info.view_id = base::GenerateGUID();
+            *payload = target_info.view_id;
+            stream_target_info_[request] = target_info;
+            return true;
+        }
+    }
+    return false;
+}
+
+// Informs the delegate that a Stream was created. The Stream can be read from
+// the blob URL of the Stream, but can only be read once.
+void ResourceDispatcherHostDelegateQt::OnStreamCreated(net::URLRequest *request,
+                                                       std::unique_ptr<content::StreamInfo> stream)
+{
+    const content::ResourceRequestInfo *info = content::ResourceRequestInfo::ForRequest(request);
+    std::map<net::URLRequest *, StreamTargetInfo>::iterator ix = stream_target_info_.find(request);
+    CHECK(ix != stream_target_info_.end());
+    int render_frame_id = -1;
+    int render_process_id = -1;
+    if (!content::ResourceRequestInfo::GetRenderFrameForRequest(request, &render_process_id, &render_frame_id)) {
+        stream_target_info_.erase(request);
+        request->Cancel();
+        return;
+    }
+
+    base::PostTaskWithTraits(
+          FROM_HERE, {content::BrowserThread::UI},
+                base::BindOnce(&OnPdfStreamIntercepted,
+                               request->url(), ix->second.extension_id,
+                               info->GetFrameTreeNodeId(), info->GetWebContentsGetterForRequest()
+                              )
+                );
+    stream_target_info_.erase(request);
+}
+
+} // namespace QtWebEngineCore
diff --git a/src/core/renderer_host/resource_dispatcher_host_delegate_qt.h b/src/core/renderer_host/resource_dispatcher_host_delegate_qt.h
new file mode 100644
index 000000000..3039fd03e
--- /dev/null
+++ b/src/core/renderer_host/resource_dispatcher_host_delegate_qt.h
@@ -0,0 +1,77 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef RESOURCE_DISPATCHER_HOST_DELEGATE_QT_H
+#define RESOURCE_DISPATCHER_HOST_DELEGATE_QT_H
+
+#include "content/public/browser/resource_dispatcher_host_delegate.h"
+#include "extensions/buildflags/buildflags.h"
+
+#include "web_contents_adapter_client.h"
+
+namespace QtWebEngineCore {
+
+class ResourceDispatcherHostDelegateQt : public content::ResourceDispatcherHostDelegate {
+public:
+    // If the stream will be rendered in a BrowserPlugin, |payload| will contain
+    // the data that should be given to the old ResourceHandler to forward to the
+    // renderer process.
+    bool ShouldInterceptResourceAsStream(net::URLRequest *request,
+                                         const std::string &mime_type,
+                                         GURL *origin,
+                                         std::string *payload) override;
+
+    // Informs the delegate that a Stream was created. The Stream can be read from
+    // the blob URL of the Stream, but can only be read once.
+    void OnStreamCreated(net::URLRequest *request,
+                         std::unique_ptr<content::StreamInfo> stream) override;
+private:
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    struct StreamTargetInfo {
+        std::string extension_id;
+        std::string view_id;
+    };
+    std::map<net::URLRequest *, StreamTargetInfo> stream_target_info_;
+#endif
+
+};
+
+} // namespace QtWebEngineCore
+
+#endif // RESOURCE_DISPATCHER_HOST_DELEGATE_QT_H
diff --git a/src/core/resource_context_qt.cpp b/src/core/resource_context_qt.cpp
index 6dfa5064e..78be72107 100644
--- a/src/core/resource_context_qt.cpp
+++ b/src/core/resource_context_qt.cpp
@@ -64,4 +64,11 @@ net::URLRequestContext* ResourceContextQt::GetRequestContext()
     return m_io_data->urlRequestContext();
 }
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+extensions::ExtensionSystemQt* ResourceContextQt::GetExtensionSystem()
+{
+    return m_io_data->GetExtensionSystem();
+}
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
 } // namespace QtWebEngineCore
diff --git a/src/core/resource_context_qt.h b/src/core/resource_context_qt.h
index 6a5e7a74e..08359c79c 100644
--- a/src/core/resource_context_qt.h
+++ b/src/core/resource_context_qt.h
@@ -42,6 +42,20 @@
 
 #include "content/public/browser/resource_context.h"
 
+#include "extensions/buildflags/buildflags.h"
+
+namespace net {
+class URLRequestContextGetter;
+}
+
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+namespace extensions {
+class ExtensionSystemQt;
+}
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
+
+class GURL;
+
 namespace QtWebEngineCore {
 
 class ProfileIODataQt;
@@ -51,6 +65,9 @@ class ResourceContextQt : public content::ResourceContext
 public:
     ResourceContextQt(ProfileIODataQt *io_data);
     net::URLRequestContext *GetRequestContext() override;
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionSystemQt* GetExtensionSystem();
+#endif // BUILDFLAG(ENABLE_EXTENSIONS)
 private:
     ProfileIODataQt* m_io_data;
     DISALLOW_COPY_AND_ASSIGN(ResourceContextQt);
diff --git a/src/core/web_contents_adapter.cpp b/src/core/web_contents_adapter.cpp
index 68bbc3daa..0c884d265 100644
--- a/src/core/web_contents_adapter.cpp
+++ b/src/core/web_contents_adapter.cpp
@@ -84,6 +84,9 @@
 #include "content/public/common/url_constants.h"
 #include "content/public/common/web_preferences.h"
 #include "content/public/common/webrtc_ip_handling_policy.h"
+#include "extensions/buildflags/buildflags.h"
+#include "third_party/blink/public/mojom/frame/find_in_page.mojom.h"
+//#include "third_party/blink/public/web/web_find_options.h"
 #include "third_party/blink/public/web/web_media_player_action.h"
 #include "printing/buildflags/buildflags.h"
 #include "ui/base/clipboard/clipboard.h"
@@ -95,6 +98,10 @@
 #include <QtWebChannel/QWebChannel>
 #endif
 
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+#include "extensions/extension_web_contents_observer_qt.h"
+#endif
+
 #include <QDir>
 #include <QGuiApplication>
 #include <QPageLayout>
@@ -507,6 +514,9 @@ void WebContentsAdapter::initialize(content::SiteInstance *site)
 #if QT_CONFIG(webengine_printing_and_pdf)
     PrintViewManagerQt::CreateForWebContents(webContents());
 #endif
+#if BUILDFLAG(ENABLE_EXTENSIONS)
+    extensions::ExtensionWebContentsObserverQt::CreateForWebContents(webContents());
+#endif
 
     // Create an instance of WebEngineVisitedLinksManager to catch the first
     // content::NOTIFICATION_RENDERER_PROCESS_CREATED event. This event will
@@ -1275,16 +1285,6 @@ void WebContentsAdapter::grantMouseLockPermission(bool granted)
     m_webContents->GotResponseToLockMouseRequest(granted);
 }
 
-void WebContentsAdapter::dpiScaleChanged()
-{
-    CHECK_INITIALIZED();
-    content::RenderWidgetHostImpl* impl = NULL;
-    if (m_webContents->GetRenderViewHost())
-        impl = content::RenderWidgetHostImpl::From(m_webContents->GetRenderViewHost()->GetWidget());
-    if (impl)
-        impl->NotifyScreenInfoChanged();
-}
-
 void WebContentsAdapter::setBackgroundColor(const QColor &color)
 {
     CHECK_INITIALIZED();
diff --git a/src/core/web_contents_adapter.h b/src/core/web_contents_adapter.h
index e8e5359be..b4a01fb17 100644
--- a/src/core/web_contents_adapter.h
+++ b/src/core/web_contents_adapter.h
@@ -184,7 +184,6 @@ public:
     void runGeolocationRequestCallback(const QUrl &securityOrigin, bool allowed);
     void grantMouseLockPermission(bool granted);
 
-    void dpiScaleChanged();
     void setBackgroundColor(const QColor &color);
     QAccessibleInterface *browserAccessible();
     ProfileQt* profile();
diff --git a/src/core/web_contents_adapter_client.h b/src/core/web_contents_adapter_client.h
index 4a36e77f9..f4937f0d4 100644
--- a/src/core/web_contents_adapter_client.h
+++ b/src/core/web_contents_adapter_client.h
@@ -424,7 +424,6 @@ public:
     virtual void selectionChanged() = 0;
     virtual void recentlyAudibleChanged(bool recentlyAudible) = 0;
     virtual QRectF viewportRect() const = 0;
-    virtual qreal dpiScale() const = 0;
     virtual QColor backgroundColor() const = 0;
     virtual void loadStarted(const QUrl &provisionalUrl, bool isErrorPage = false) = 0;
     virtual void loadCommitted() = 0;
diff --git a/src/core/web_contents_view_qt.cpp b/src/core/web_contents_view_qt.cpp
index 648e0fd8f..550a98a52 100644
--- a/src/core/web_contents_view_qt.cpp
+++ b/src/core/web_contents_view_qt.cpp
@@ -239,7 +239,7 @@ void WebContentsViewQt::StartDragging(const content::DropData &drop_data,
 
     QPixmap pixmap;
     QPoint hotspot;
-    pixmap = QPixmap::fromImage(toQImage(image.GetRepresentation(m_client->dpiScale())));
+    pixmap = QPixmap::fromImage(toQImage(image.GetRepresentation(1.0)));
     if (!pixmap.isNull()) {
         hotspot.setX(image_offset.x());
         hotspot.setY(image_offset.y());
diff --git a/src/core/web_engine_context.cpp b/src/core/web_engine_context.cpp
index 90b1bffa5..63a1637fe 100644
--- a/src/core/web_engine_context.cpp
+++ b/src/core/web_engine_context.cpp
@@ -51,6 +51,7 @@
 #include "cc/base/switches.h"
 #if QT_CONFIG(webengine_printing_and_pdf)
 #include "chrome/browser/printing/print_job_manager.h"
+#include "components/printing/browser/features.h"
 #endif
 #include "components/viz/common/features.h"
 #include "components/web_cache/browser/web_cache_manager.h"
@@ -457,6 +458,10 @@ WebEngineContext::WebEngineContext()
 
     appendToFeatureSwitch(parsedCommandLine, switches::kDisableFeatures, features::kBackgroundFetch.name);
 
+#if QT_CONFIG(webengine_printing_and_pdf)
+    appendToFeatureSwitch(parsedCommandLine, switches::kDisableFeatures, printing::features::kUsePdfCompositorServiceForPrint.name);
+#endif
+
     if (useEmbeddedSwitches) {
         // embedded switches are based on the switches for Android, see content/browser/android/content_startup_flags.cc
         appendToFeatureSwitch(parsedCommandLine, switches::kEnableFeatures, features::kOverlayScrollbar.name);
diff --git a/src/core/web_event_factory.cpp b/src/core/web_event_factory.cpp
index 339a3ef0e..b97696030 100644
--- a/src/core/web_event_factory.cpp
+++ b/src/core/web_event_factory.cpp
@@ -1354,10 +1354,10 @@ static WebPointerProperties::PointerType pointerTypeForTabletEvent(const QTablet
 }
 #endif
 
-WebMouseEvent WebEventFactory::toWebMouseEvent(QMouseEvent *ev, double dpiScale)
+WebMouseEvent WebEventFactory::toWebMouseEvent(QMouseEvent *ev)
 {
     WebMouseEvent webKitEvent(webEventTypeForEvent(ev),
-                              WebFloatPoint(ev->x() / dpiScale, ev->y() / dpiScale),
+                              WebFloatPoint(ev->x(), ev->y()),
                               WebFloatPoint(ev->globalX(), ev->globalY()),
                               mouseButtonForEvent<QMouseEvent>(ev),
                               0,
@@ -1369,14 +1369,14 @@ WebMouseEvent WebEventFactory::toWebMouseEvent(QMouseEvent *ev, double dpiScale)
     return webKitEvent;
 }
 
-WebMouseEvent WebEventFactory::toWebMouseEvent(QHoverEvent *ev, double dpiScale)
+WebMouseEvent WebEventFactory::toWebMouseEvent(QHoverEvent *ev)
 {
     WebMouseEvent webKitEvent;
     webKitEvent.SetTimeStamp(base::TimeTicks::Now());
     webKitEvent.SetModifiers(modifiersForEvent(ev));
     webKitEvent.SetType(webEventTypeForEvent(ev));
 
-    webKitEvent.SetPositionInWidget(ev->pos().x() / dpiScale, ev->pos().y() / dpiScale);
+    webKitEvent.SetPositionInWidget(ev->pos().x(), ev->pos().y());
     webKitEvent.movement_x = ev->pos().x() - ev->oldPos().x();
     webKitEvent.movement_y = ev->pos().y() - ev->oldPos().y();
     webKitEvent.pointer_type = WebPointerProperties::PointerType::kMouse;
@@ -1385,10 +1385,10 @@ WebMouseEvent WebEventFactory::toWebMouseEvent(QHoverEvent *ev, double dpiScale)
 }
 
 #if QT_CONFIG(tabletevent)
-WebMouseEvent WebEventFactory::toWebMouseEvent(QTabletEvent *ev, double dpiScale)
+WebMouseEvent WebEventFactory::toWebMouseEvent(QTabletEvent *ev)
 {
     WebMouseEvent webKitEvent(webEventTypeForEvent(ev),
-                              WebFloatPoint(ev->x() / dpiScale, ev->y() / dpiScale),
+                              WebFloatPoint(ev->x(), ev->y()),
                               WebFloatPoint(ev->globalX(), ev->globalY()),
                               mouseButtonForEvent<QTabletEvent>(ev),
                               0,
@@ -1416,17 +1416,17 @@ WebMouseEvent WebEventFactory::toWebMouseEvent(QEvent *ev)
 }
 
 #ifndef QT_NO_GESTURES
-WebGestureEvent WebEventFactory::toWebGestureEvent(QNativeGestureEvent *ev, double dpiScale)
+WebGestureEvent WebEventFactory::toWebGestureEvent(QNativeGestureEvent *ev)
 {
     WebGestureEvent webKitEvent;
     webKitEvent.SetTimeStamp(base::TimeTicks::Now());
     webKitEvent.SetModifiers(modifiersForEvent(ev));
 
-    webKitEvent.SetPositionInWidget(WebFloatPoint(ev->localPos().x() / dpiScale,
-                                                  ev->localPos().y() / dpiScale));
+    webKitEvent.SetPositionInWidget(WebFloatPoint(ev->localPos().x(),
+                                                  ev->localPos().y()));
 
-    webKitEvent.SetPositionInScreen(WebFloatPoint(ev->screenPos().x() / dpiScale,
-                                                  ev->screenPos().y() / dpiScale));
+    webKitEvent.SetPositionInScreen(WebFloatPoint(ev->screenPos().x(),
+                                                  ev->screenPos().y()));
 
     webKitEvent.SetSourceDevice(blink::kWebGestureDeviceTouchpad);
 
@@ -1484,13 +1484,13 @@ blink::WebMouseWheelEvent::Phase toBlinkPhase(QWheelEvent *ev)
     return blink::WebMouseWheelEvent::kPhaseNone;
 }
 
-blink::WebMouseWheelEvent WebEventFactory::toWebWheelEvent(QWheelEvent *ev, double dpiScale)
+blink::WebMouseWheelEvent WebEventFactory::toWebWheelEvent(QWheelEvent *ev)
 {
     WebMouseWheelEvent webEvent;
     webEvent.SetType(webEventTypeForEvent(ev));
     webEvent.SetModifiers(modifiersForEvent(ev));
     webEvent.SetTimeStamp(base::TimeTicks::Now());
-    webEvent.SetPositionInWidget(ev->x() / dpiScale, ev->y() / dpiScale);
+    webEvent.SetPositionInWidget(ev->x(), ev->y());
     webEvent.SetPositionInScreen(ev->globalX(), ev->globalY());
 
     webEvent.wheel_ticks_x = static_cast<float>(ev->angleDelta().x()) / QWheelEvent::DefaultDeltasPerStep;
@@ -1506,7 +1506,7 @@ blink::WebMouseWheelEvent WebEventFactory::toWebWheelEvent(QWheelEvent *ev, doub
     return webEvent;
 }
 
-bool WebEventFactory::coalesceWebWheelEvent(blink::WebMouseWheelEvent &webEvent, QWheelEvent *ev, double dpiScale)
+bool WebEventFactory::coalesceWebWheelEvent(blink::WebMouseWheelEvent &webEvent, QWheelEvent *ev)
 {
     if (webEventTypeForEvent(ev) != webEvent.GetType())
         return false;
@@ -1520,7 +1520,7 @@ bool WebEventFactory::coalesceWebWheelEvent(blink::WebMouseWheelEvent &webEvent,
 #endif
 
     webEvent.SetTimeStamp(base::TimeTicks::Now());
-    webEvent.SetPositionInWidget(ev->x() / dpiScale, ev->y() / dpiScale);
+    webEvent.SetPositionInWidget(ev->x(), ev->y());
     webEvent.SetPositionInScreen(ev->globalX(), ev->globalY());
 
     webEvent.wheel_ticks_x += static_cast<float>(ev->angleDelta().x()) / QWheelEvent::DefaultDeltasPerStep;
diff --git a/src/core/web_event_factory.h b/src/core/web_event_factory.h
index 4b22de7d7..526202cfb 100644
--- a/src/core/web_event_factory.h
+++ b/src/core/web_event_factory.h
@@ -66,17 +66,17 @@ QT_END_NAMESPACE
 class WebEventFactory {
 
 public:
-    static blink::WebMouseEvent toWebMouseEvent(QMouseEvent*, double dpiScale);
-    static blink::WebMouseEvent toWebMouseEvent(QHoverEvent*, double dpiScale);
+    static blink::WebMouseEvent toWebMouseEvent(QMouseEvent *);
+    static blink::WebMouseEvent toWebMouseEvent(QHoverEvent *);
 #ifndef QT_NO_TABLETEVENT
-    static blink::WebMouseEvent toWebMouseEvent(QTabletEvent*, double dpiScale);
+    static blink::WebMouseEvent toWebMouseEvent(QTabletEvent *);
 #endif
     static blink::WebMouseEvent toWebMouseEvent(QEvent *);
 #ifndef QT_NO_GESTURES
-    static blink::WebGestureEvent toWebGestureEvent(QNativeGestureEvent *, double dpiScale);
+    static blink::WebGestureEvent toWebGestureEvent(QNativeGestureEvent *);
 #endif
-    static blink::WebMouseWheelEvent toWebWheelEvent(QWheelEvent*, double dpiScale);
-    static bool coalesceWebWheelEvent(blink::WebMouseWheelEvent &, QWheelEvent*, double dpiScale);
+    static blink::WebMouseWheelEvent toWebWheelEvent(QWheelEvent *);
+    static bool coalesceWebWheelEvent(blink::WebMouseWheelEvent &, QWheelEvent *);
     static content::NativeWebKeyboardEvent toWebKeyboardEvent(QKeyEvent*);
     static bool getEditCommand(QKeyEvent *event, std::string *editCommand);
 };
diff --git a/src/webengine/api/qquickwebengineview.cpp b/src/webengine/api/qquickwebengineview.cpp
index 59431cadc..5e6a45924 100644
--- a/src/webengine/api/qquickwebengineview.cpp
+++ b/src/webengine/api/qquickwebengineview.cpp
@@ -128,7 +128,6 @@ QQuickWebEngineViewPrivate::QQuickWebEngineViewPrivate()
     , m_webChannel(0)
     , m_webChannelWorld(0)
     , m_isBeingAdopted(false)
-    , m_dpiScale(1.0)
     , m_backgroundColor(Qt::white)
     , m_zoomFactor(1.0)
     , m_ui2Enabled(false)
@@ -415,11 +414,6 @@ QRectF QQuickWebEngineViewPrivate::viewportRect() const
     return QRectF(q->x(), q->y(), q->width(), q->height());
 }
 
-qreal QQuickWebEngineViewPrivate::dpiScale() const
-{
-    return m_dpiScale;
-}
-
 QColor QQuickWebEngineViewPrivate::backgroundColor() const
 {
     return m_backgroundColor;
diff --git a/src/webengine/api/qquickwebengineview_p_p.h b/src/webengine/api/qquickwebengineview_p_p.h
index 3c985cba1..4e8657651 100644
--- a/src/webengine/api/qquickwebengineview_p_p.h
+++ b/src/webengine/api/qquickwebengineview_p_p.h
@@ -109,7 +109,6 @@ public:
     void selectionChanged() override { }
     void recentlyAudibleChanged(bool recentlyAudible) override;
     QRectF viewportRect() const override;
-    qreal dpiScale() const override;
     QColor backgroundColor() const override;
     void loadStarted(const QUrl &provisionalUrl, bool isErrorPage = false) override;
     void loadCommitted() override;
@@ -218,7 +217,6 @@ public:
 private:
     QScopedPointer<QtWebEngineCore::UIDelegatesManager> m_uIDelegatesManager;
     QList<QQuickWebEngineScript *> m_userScripts;
-    qreal m_dpiScale;
     QColor m_backgroundColor;
     qreal m_zoomFactor;
     bool m_ui2Enabled;
diff --git a/src/webenginewidgets/api/qwebenginepage.cpp b/src/webenginewidgets/api/qwebenginepage.cpp
index 5940319c3..22ef8fffe 100644
--- a/src/webenginewidgets/api/qwebenginepage.cpp
+++ b/src/webenginewidgets/api/qwebenginepage.cpp
@@ -267,11 +267,6 @@ QRectF QWebEnginePagePrivate::viewportRect() const
     return view ? view->rect() : QRectF();
 }
 
-qreal QWebEnginePagePrivate::dpiScale() const
-{
-    return 1.0;
-}
-
 QColor QWebEnginePagePrivate::backgroundColor() const
 {
     return m_backgroundColor;
diff --git a/src/webenginewidgets/api/qwebenginepage_p.h b/src/webenginewidgets/api/qwebenginepage_p.h
index e60438d97..bf2f43f80 100644
--- a/src/webenginewidgets/api/qwebenginepage_p.h
+++ b/src/webenginewidgets/api/qwebenginepage_p.h
@@ -100,7 +100,6 @@ public:
     void selectionChanged() override;
     void recentlyAudibleChanged(bool recentlyAudible) override;
     QRectF viewportRect() const override;
-    qreal dpiScale() const override;
     QColor backgroundColor() const override;
     void loadStarted(const QUrl &provisionalUrl, bool isErrorPage = false) override;
     void loadCommitted() override { }
diff --git a/tools/buildscripts/repack_locales.py b/tools/buildscripts/repack_locales.py
index 103fdaf69..8f1ae190b 100755
--- a/tools/buildscripts/repack_locales.py
+++ b/tools/buildscripts/repack_locales.py
@@ -56,6 +56,8 @@ INT_DIR = None
 # The target platform. If it is not defined, sys.platform will be used.
 OS = None
 
+ENABLE_EXTENSIONS = False
+
 # Extra input files.
 EXTRA_INPUT_FILES = []
 
@@ -109,6 +111,14 @@ def calc_inputs(locale):
     inputs.append(os.path.join(SHARE_INT_DIR, 'chrome',
                   'chromium_strings_%s.pak' % locale))
 
+  if ENABLE_EXTENSIONS:
+    # For example:
+    # '<(SHARED_INTERMEDIATE_DIR)/extensions/strings/extensions_strings_da.pak
+    # TODO(jamescook): When Android stops building extensions code move this
+    # to the OS != 'ios' and OS != 'android' section below.
+    inputs.append(os.path.join(SHARE_INT_DIR, 'extensions', 'strings',
+                  'extensions_strings_%s.pak' % locale))
+
   # Add any extra input files.
   for extra_file in EXTRA_INPUT_FILES:
     inputs.append('%s_%s.pak' % (extra_file, locale))
@@ -158,6 +168,7 @@ def DoMain(argv):
   global INT_DIR
   global OS
   global EXTRA_INPUT_FILES
+  global ENABLE_EXTENSIONS
 
   parser = optparse.OptionParser("usage: %prog [options] locales")
   parser.add_option("-i", action="store_true", dest="inputs", default=False,
@@ -177,6 +188,9 @@ def DoMain(argv):
                          locale suffix and \".pak\" extension.")
   parser.add_option("-p", action="store", dest="os",
                     help="The target OS. (e.g. mac, linux, win, etc.)")
+  parser.add_option("--enable-extensions", action="store",
+                    dest="enable_extensions",
+                    help="Whether to include strings for extensions")
   options, locales = parser.parse_args(argv)
 
   if not locales:
@@ -188,6 +202,7 @@ def DoMain(argv):
   SHARE_INT_DIR = options.share_int_dir
   EXTRA_INPUT_FILES = options.extra_input
   OS = options.os
+  ENABLE_EXTENSIONS = options.enable_extensions == '1'
 
   if not OS:
     if sys.platform == 'darwin':