4 files changed, 29 insertions, 2 deletions
diff --git a/src/plugins/platforms/xcb/qxcbconnection.cpp b/src/plugins/platforms/xcb/qxcbconnection.cpp
index f93cfde4a5..abb48034cd 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection.cpp
@@ -556,6 +556,7 @@ QXcbConnection::QXcbConnection(QXcbNativeInterface *nativeInterface, bool canGra
     , has_xkb(false)
     , m_buttons(0)
     , m_focusWindow(0)
+    , m_mouseGrabber(0)
     , m_clientLeader(0)
     , m_systemTrayTracker(0)
     , m_glIntegration(Q_NULLPTR)
@@ -1352,6 +1353,10 @@ void QXcbConnection::setFocusWindow(QXcbWindow *w)
 {
     m_focusWindow = w;
 }
+void QXcbConnection::setMouseGrabber(QXcbWindow *w)
+{
+    m_mouseGrabber = w;
+}
 
 void QXcbConnection::grabServer()
 {
diff --git a/src/plugins/platforms/xcb/qxcbconnection.h b/src/plugins/platforms/xcb/qxcbconnection.h
index 6d26e88fa2..a6a7b9e7ca 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.h
+++ b/src/plugins/platforms/xcb/qxcbconnection.h
@@ -469,6 +469,8 @@ public:
 
     QXcbWindow *focusWindow() const { return m_focusWindow; }
     void setFocusWindow(QXcbWindow *);
+    QXcbWindow *mouseGrabber() const { return m_mouseGrabber; }
+    void setMouseGrabber(QXcbWindow *);
 
     QByteArray startupId() const { return m_startupId; }
     void setStartupId(const QByteArray &nextId) { m_startupId = nextId; }
@@ -649,6 +651,7 @@ private:
     Qt::MouseButtons m_buttons;
 
     QXcbWindow *m_focusWindow;
+    QXcbWindow *m_mouseGrabber;
 
     xcb_window_t m_clientLeader;
     QByteArray m_startupId;
diff --git a/src/plugins/platforms/xcb/qxcbdrag.cpp b/src/plugins/platforms/xcb/qxcbdrag.cpp
index d19ea241f1..9296a6d141 100644
--- a/src/plugins/platforms/xcb/qxcbdrag.cpp
+++ b/src/plugins/platforms/xcb/qxcbdrag.cpp
@@ -194,6 +194,8 @@ void QXcbDrag::startDrag()
 
     setUseCompositing(current_virtual_desktop->compositingActive());
     QBasicDrag::startDrag();
+    if (connection()->mouseGrabber() == Q_NULLPTR)
+        shapedPixmapWindow()->setMouseGrabEnabled(true);
 }
 
 void QXcbDrag::endDrag()
diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index bec167fec2..4e4a0cdaef 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -594,12 +594,16 @@ QXcbWindow::~QXcbWindow()
 {
     if (window()->type() != Qt::ForeignWindow)
         destroy();
+    else if (connection()->mouseGrabber() == this)
+        connection()->setMouseGrabber(Q_NULLPTR);
 }
 
 void QXcbWindow::destroy()
 {
     if (connection()->focusWindow() == this)
         doFocusOut();
+    if (connection()->mouseGrabber() == this)
+        connection()->setMouseGrabber(Q_NULLPTR);
 
     if (m_syncCounter && m_usingSyncProtocol)
         Q_XCB_CALL(xcb_sync_destroy_counter(xcb_connection(), m_syncCounter));
@@ -847,6 +851,9 @@ void QXcbWindow::hide()
 
     xcb_flush(xcb_connection());
 
+    if (connection()->mouseGrabber() == this)
+        connection()->setMouseGrabber(Q_NULLPTR);
+
     m_mapped = false;
 }
 
@@ -2357,6 +2364,8 @@ void QXcbWindow::handlePropertyNotifyEvent(const xcb_property_notify_event_t *ev
             QWindowSystemInterface::handleWindowStateChanged(window(), newState);
             m_lastWindowStateEvent = newState;
             m_windowState = newState;
+            if (m_windowState == Qt::WindowMinimized && connection()->mouseGrabber() == this)
+                connection()->setMouseGrabber(Q_NULLPTR);
         }
         return;
     } else if (event->atom == atom(QXcbAtom::_NET_FRAME_EXTENTS)) {
@@ -2411,9 +2420,15 @@ bool QXcbWindow::setKeyboardGrabEnabled(bool grab)
 
 bool QXcbWindow::setMouseGrabEnabled(bool grab)
 {
+    if (!grab && connection()->mouseGrabber() == this)
+        connection()->setMouseGrabber(Q_NULLPTR);
 #ifdef XCB_USE_XINPUT22
-    if (connection()->xi2MouseEvents())
-        return connection()->xi2SetMouseGrabEnabled(m_window, grab);
+    if (connection()->xi2MouseEvents()) {
+        bool result = connection()->xi2SetMouseGrabEnabled(m_window, grab);
+        if (grab && result)
+            connection()->setMouseGrabber(this);
+        return result;
+    }
 #endif
     if (grab && !connection()->canGrab())
         return false;
@@ -2432,6 +2447,8 @@ bool QXcbWindow::setMouseGrabEnabled(bool grab)
     xcb_grab_pointer_reply_t *reply = xcb_grab_pointer_reply(xcb_connection(), cookie, NULL);
     bool result = !(!reply || reply->status != XCB_GRAB_STATUS_SUCCESS);
     free(reply);
+    if (result)
+        connection()->setMouseGrabber(this);
     return result;
 }