Merge remote-tracking branch 'origin/wip/qt6' into wip/cmake

Change-Id: I715b1d743d5f11560e7b3fbeb8fd64a5e5ddb277

31 files changed, 330 insertions, 170 deletions

diff --git a/src/widgets/widgets/qabstractscrollarea.cpp b/src/widgets/widgets/qabstractscrollarea.cpp
index 5ea8330db2..b9e0d3280f 100644
--- a/src/widgets/widgets/qabstractscrollarea.cpp
+++ b/src/widgets/widgets/qabstractscrollarea.cpp
@@ -1086,7 +1086,7 @@ bool QAbstractScrollArea::event(QEvent *e)
             QScrollBar *vBar = verticalScrollBar();
             QPointF delta = g->delta();
             if (!delta.isNull()) {
-                if (QApplication::isRightToLeft())
+                if (QGuiApplication::isRightToLeft())
                     delta.rx() *= -1;
                 int newX = hBar->value() - delta.x();
                 int newY = vBar->value() - delta.y();
@@ -1325,9 +1325,9 @@ void QAbstractScrollArea::wheelEvent(QWheelEvent *e)
 {
     Q_D(QAbstractScrollArea);
     if (e->orientation() == Qt::Horizontal)
-        QApplication::sendEvent(d->hbar, e);
+        QCoreApplication::sendEvent(d->hbar, e);
     else
-        QApplication::sendEvent(d->vbar, e);
+        QCoreApplication::sendEvent(d->vbar, e);
 }
 #endif
 
diff --git a/src/widgets/widgets/qabstractspinbox.cpp b/src/widgets/widgets/qabstractspinbox.cpp
index 04276aa400..e6e9939a10 100644
--- a/src/widgets/widgets/qabstractspinbox.cpp
+++ b/src/widgets/widgets/qabstractspinbox.cpp
@@ -333,7 +333,7 @@ void QAbstractSpinBox::setReadOnly(bool enable)
     d->readOnly = enable;
     d->edit->setReadOnly(enable);
     QEvent event(QEvent::ReadOnlyChange);
-    QApplication::sendEvent(this, &event);
+    QCoreApplication::sendEvent(this, &event);
     update();
 }
 
@@ -574,10 +574,10 @@ QAbstractSpinBox::StepEnabled QAbstractSpinBox::stepEnabled() const
     if (d->wrapping)
         return StepEnabled(StepUpEnabled | StepDownEnabled);
     StepEnabled ret = StepNone;
-    if (d->variantCompare(d->value, d->maximum) < 0) {
+    if (QAbstractSpinBoxPrivate::variantCompare(d->value, d->maximum) < 0) {
         ret |= StepUpEnabled;
     }
-    if (d->variantCompare(d->value, d->minimum) > 0) {
+    if (QAbstractSpinBoxPrivate::variantCompare(d->value, d->minimum) > 0) {
         ret |= StepDownEnabled;
     }
     return ret;
diff --git a/src/widgets/widgets/qcombobox.cpp b/src/widgets/widgets/qcombobox.cpp
index 07c55e4db6..0b52747b6a 100644
--- a/src/widgets/widgets/qcombobox.cpp
+++ b/src/widgets/widgets/qcombobox.cpp
@@ -1521,7 +1521,7 @@ int QComboBox::maxCount() const
 /*!
     \obsolete
 
-    Use setCompleter() instead.
+    Use completer() instead.
 */
 bool QComboBox::autoCompletion() const
 {
@@ -1881,12 +1881,11 @@ void QComboBox::setLineEdit(QLineEdit *edit)
     d->updateFocusPolicy();
     d->lineEdit->setFocusProxy(this);
     d->lineEdit->setAttribute(Qt::WA_MacShowFocusRect, false);
+#if QT_DEPRECATED_SINCE(5, 13)
 #if QT_CONFIG(completer)
     setAutoCompletion(d->autoCompletion);
-#endif
 
 #ifdef QT_KEYPAD_NAVIGATION
-#if QT_CONFIG(completer)
     if (QApplication::keypadNavigationEnabled()) {
         // Editable combo boxes will have a completer that is set to UnfilteredPopupCompletion.
         // This means that when the user enters edit mode they are immediately presented with a
@@ -1899,6 +1898,7 @@ void QComboBox::setLineEdit(QLineEdit *edit)
     }
 #endif
 #endif
+#endif
 
     setAttribute(Qt::WA_InputMethodEnabled);
     d->updateLayoutDirection();
@@ -2618,7 +2618,7 @@ bool QComboBoxPrivate::showNativePopup()
     // We need to fake one here to un-press the button.
     QMouseEvent mouseReleased(QEvent::MouseButtonRelease, q->pos(), Qt::LeftButton,
                               Qt::MouseButtons(Qt::LeftButton), Qt::KeyboardModifiers());
-    qApp->sendEvent(q, &mouseReleased);
+    QCoreApplication::sendEvent(q, &mouseReleased);
 #endif
 
     return true;
@@ -2838,19 +2838,15 @@ void QComboBox::showPopup()
     bool startTimer = !container->isVisible();
     container->raise();
     container->create();
-    QWindow *containerWindow = container->window()->windowHandle();
-    if (containerWindow) {
-        QWindow *win = window()->windowHandle();
-        if (win) {
-            QScreen *currentScreen = win->screen();
-            if (currentScreen && !currentScreen->virtualSiblings().contains(containerWindow->screen())) {
-                containerWindow->setScreen(currentScreen);
-
-                // This seems to workaround an issue in xcb+multi GPU+multiscreen
-                // environment where the window might not always show up when screen
-                // is changed.
-                container->hide();
-            }
+    if (QWindow *containerWindow = qt_widget_private(container)->windowHandle(QWidgetPrivate::WindowHandleMode::TopLevel)) {
+        QScreen *currentScreen = d->associatedScreen();
+        if (currentScreen && !currentScreen->virtualSiblings().contains(containerWindow->screen())) {
+            containerWindow->setScreen(currentScreen);
+
+            // This seems to workaround an issue in xcb+multi GPU+multiscreen
+            // environment where the window might not always show up when screen
+            // is changed.
+            container->hide();
         }
     }
     container->show();
@@ -2919,7 +2915,7 @@ void QComboBox::hidePopup()
         bool didFade = false;
         if (needFade) {
 #if defined(Q_OS_MAC)
-            QPlatformNativeInterface *platformNativeInterface = qApp->platformNativeInterface();
+            QPlatformNativeInterface *platformNativeInterface = QGuiApplication::platformNativeInterface();
             int at = platformNativeInterface->metaObject()->indexOfMethod("fadeWindow()");
             if (at != -1) {
                 QMetaMethod windowFade = platformNativeInterface->metaObject()->method(at);
diff --git a/src/widgets/widgets/qcombobox.h b/src/widgets/widgets/qcombobox.h
index 37b155774d..3b48b151a1 100644
--- a/src/widgets/widgets/qcombobox.h
+++ b/src/widgets/widgets/qcombobox.h
@@ -96,10 +96,13 @@ public:
 
 #if QT_CONFIG(completer)
 #if QT_DEPRECATED_SINCE(5, 13)
+    QT_DEPRECATED_X("Use completer() instead.")
     bool autoCompletion() const;
+    QT_DEPRECATED_X("Use setCompleter() instead.")
     void setAutoCompletion(bool enable);
-
+    QT_DEPRECATED_X("Use completer()->caseSensitivity() instead.")
     Qt::CaseSensitivity autoCompletionCaseSensitivity() const;
+    QT_DEPRECATED_X("Use completer()->setCaseSensitivity() instead.")
     void setAutoCompletionCaseSensitivity(Qt::CaseSensitivity sensitivity);
 #endif
 #endif
diff --git a/src/widgets/widgets/qdatetimeedit.cpp b/src/widgets/widgets/qdatetimeedit.cpp
index 3f41fdeb59..45c72e24d4 100644
--- a/src/widgets/widgets/qdatetimeedit.cpp
+++ b/src/widgets/widgets/qdatetimeedit.cpp
@@ -645,7 +645,7 @@ QDateTimeEdit::Section QDateTimeEdit::currentSection() const
     if (QApplication::keypadNavigationEnabled() && d->focusOnButton)
         return NoSection;
 #endif
-    return d->convertToPublic(d->sectionType(d->currentSectionIndex));
+    return QDateTimeEditPrivate::convertToPublic(d->sectionType(d->currentSectionIndex));
 }
 
 void QDateTimeEdit::setCurrentSection(Section section)
@@ -659,7 +659,7 @@ void QDateTimeEdit::setCurrentSection(Section section)
     int index = d->currentSectionIndex + 1;
     for (int i=0; i<2; ++i) {
         while (index < size) {
-            if (d->convertToPublic(d->sectionType(index)) == section) {
+            if (QDateTimeEditPrivate::convertToPublic(d->sectionType(index)) == section) {
                 d->edit->setCursorPosition(d->sectionPos(index));
                 QDTEDEBUG << d->sectionPos(index);
                 return;
@@ -685,7 +685,7 @@ QDateTimeEdit::Section QDateTimeEdit::sectionAt(int index) const
     Q_D(const QDateTimeEdit);
     if (index < 0 || index >= d->sectionNodes.size())
         return NoSection;
-    return d->convertToPublic(d->sectionType(index));
+    return QDateTimeEditPrivate::convertToPublic(d->sectionType(index));
 }
 
 /*!
@@ -879,7 +879,7 @@ void QDateTimeEdit::setDisplayFormat(const QString &format)
         }
 
         d->formatExplicitlySet = true;
-        d->sections = d->convertSections(d->display);
+        d->sections = QDateTimeEditPrivate::convertSections(d->display);
         d->clearCache();
 
         d->currentSectionIndex = qMin(d->currentSectionIndex, d->sectionNodes.size() - 1);
@@ -1529,7 +1529,7 @@ void QDateTimeEdit::mousePressEvent(QMouseEvent *event)
 QTimeEdit::QTimeEdit(QWidget *parent)
     : QDateTimeEdit(QDATETIMEEDIT_TIME_MIN, QVariant::Time, parent)
 {
-    connect(this, SIGNAL(timeChanged(QTime)), SIGNAL(userTimeChanged(QTime)));
+    connect(this, &QTimeEdit::timeChanged, this, &QTimeEdit::userTimeChanged);
 }
 
 /*!
@@ -1540,6 +1540,7 @@ QTimeEdit::QTimeEdit(QWidget *parent)
 QTimeEdit::QTimeEdit(const QTime &time, QWidget *parent)
     : QDateTimeEdit(time, QVariant::Time, parent)
 {
+    connect(this, &QTimeEdit::timeChanged, this, &QTimeEdit::userTimeChanged);
 }
 
 /*!
@@ -1598,7 +1599,7 @@ QTimeEdit::~QTimeEdit()
 QDateEdit::QDateEdit(QWidget *parent)
     : QDateTimeEdit(QDATETIMEEDIT_DATE_INITIAL, QVariant::Date, parent)
 {
-    connect(this, SIGNAL(dateChanged(QDate)), SIGNAL(userDateChanged(QDate)));
+    connect(this, &QDateEdit::dateChanged, this, &QDateEdit::userDateChanged);
 }
 
 /*!
@@ -1609,6 +1610,7 @@ QDateEdit::QDateEdit(QWidget *parent)
 QDateEdit::QDateEdit(const QDate &date, QWidget *parent)
     : QDateTimeEdit(date, QVariant::Date, parent)
 {
+    connect(this, &QDateEdit::dateChanged, this, &QDateEdit::userDateChanged);
 }
 
 /*!
@@ -2304,13 +2306,31 @@ void QDateTimeEdit::paintEvent(QPaintEvent *event)
     style()->drawComplexControl(QStyle::CC_ComboBox, &optCombo, &p, this);
 }
 
+/*
+    Returns the string for AM and PM markers.
+
+    If a translation for "AM" and "PM" is installed, then use that.
+    Otherwise, use the default implementation, which uses the locale.
+*/
 QString QDateTimeEditPrivate::getAmPmText(AmPm ap, Case cs) const
 {
+    QString original;
+    QString translated;
     if (ap == AmText) {
-        return (cs == UpperCase ? QDateTimeParser::tr("AM") : QDateTimeParser::tr("am"));
+        original = QLatin1String(cs == UpperCase ? "AM" : "am");
+        translated = (cs == UpperCase ? QDateTimeParser::tr("AM") : QDateTimeParser::tr("am"));
     } else {
-        return (cs == UpperCase ? QDateTimeParser::tr("PM") : QDateTimeParser::tr("pm"));
+        original = QLatin1String(cs == UpperCase ? "PM" : "pm");
+        translated = (cs == UpperCase ? QDateTimeParser::tr("PM") : QDateTimeParser::tr("pm"));
     }
+
+    // This logic fails if a translation exists but doesn't change the string,
+    // which we can accept as a corner-case for which a locale-derived answer
+    // will be acceptable.
+    if (original != translated)
+        return translated;
+
+    return QDateTimeParser::getAmPmText(ap, cs);
 }
 
 int QDateTimeEditPrivate::absoluteIndex(QDateTimeEdit::Section s, int index) const
diff --git a/src/widgets/widgets/qdockarealayout.cpp b/src/widgets/widgets/qdockarealayout.cpp
index 54504d124b..55ae42db04 100644
--- a/src/widgets/widgets/qdockarealayout.cpp
+++ b/src/widgets/widgets/qdockarealayout.cpp
@@ -1678,12 +1678,9 @@ int QDockAreaLayoutInfo::prev(int index) const
     return -1;
 }
 
+#if QT_CONFIG(tabbar)
 void QDockAreaLayoutInfo::tab(int index, QLayoutItem *dockWidgetItem)
 {
-#if !QT_CONFIG(tabbar)
-    Q_UNUSED(index);
-    Q_UNUSED(dockWidgetItem);
-#else
     if (tabbed) {
         item_list.append(QDockAreaLayoutItem(dockWidgetItem));
         updateTabBar();
@@ -1699,8 +1696,8 @@ void QDockAreaLayoutInfo::tab(int index, QLayoutItem *dockWidgetItem)
         new_info->updateTabBar();
         new_info->setCurrentTab(dockWidgetItem->widget());
     }
-#endif // QT_CONFIG(tabbar)
 }
+#endif // QT_CONFIG(tabbar)
 
 void QDockAreaLayoutInfo::split(int index, Qt::Orientation orientation,
                                        QLayoutItem *dockWidgetItem)
@@ -3137,6 +3134,7 @@ void QDockAreaLayout::addDockWidget(QInternal::DockPosition pos, QDockWidget *do
     removePlaceHolder(dockWidget->objectName());
 }
 
+#if QT_CONFIG(tabbar)
 void QDockAreaLayout::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
 {
     const QList<int> path = indexOf(first);
@@ -3149,6 +3147,7 @@ void QDockAreaLayout::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
 
     removePlaceHolder(second->objectName());
 }
+#endif // QT_CONFIG(tabbar)
 
 void QDockAreaLayout::resizeDocks(const QList<QDockWidget *> &docks,
                                   const QList<int> &sizes, Qt::Orientation o)
diff --git a/src/widgets/widgets/qdockarealayout_p.h b/src/widgets/widgets/qdockarealayout_p.h
index ab9c0c476c..81384bd1b7 100644
--- a/src/widgets/widgets/qdockarealayout_p.h
+++ b/src/widgets/widgets/qdockarealayout_p.h
@@ -144,7 +144,9 @@ public:
     void remove(const QList<int> &path);
     void unnest(int index);
     void split(int index, Qt::Orientation orientation, QLayoutItem *dockWidgetItem);
+#if QT_CONFIG(tabbar)
     void tab(int index, QLayoutItem *dockWidgetItem);
+#endif
     QDockAreaLayoutItem &item(const QList<int> &path);
     QDockAreaLayoutInfo *info(const QList<int> &path);
     QDockAreaLayoutInfo *info(QWidget *widget);
@@ -275,7 +277,9 @@ public:
     bool restoreDockWidget(QDockWidget *dockWidget);
     void splitDockWidget(QDockWidget *after, QDockWidget *dockWidget,
                          Qt::Orientation orientation);
+#if QT_CONFIG(tabbar)
     void tabifyDockWidget(QDockWidget *first, QDockWidget *second);
+#endif
     void resizeDocks(const QList<QDockWidget *> &docks, const QList<int> &sizes, Qt::Orientation o);
 
     void apply(bool animate);
diff --git a/src/widgets/widgets/qdockwidget.cpp b/src/widgets/widgets/qdockwidget.cpp
index f98e0e44db..28a7cee2a0 100644
--- a/src/widgets/widgets/qdockwidget.cpp
+++ b/src/widgets/widgets/qdockwidget.cpp
@@ -267,9 +267,11 @@ QDockWidgetLayout::~QDockWidgetLayout()
 bool QDockWidgetLayout::nativeWindowDeco() const
 {
     bool floating = parentWidget()->isWindow();
+#if QT_CONFIG(tabbar)
     if (auto groupWindow =
             qobject_cast<const QDockWidgetGroupWindow *>(parentWidget()->parentWidget()))
         floating = floating || groupWindow->tabLayoutInfo();
+#endif
     return nativeWindowDeco(floating);
 }
 
@@ -1535,10 +1537,10 @@ bool QDockWidget::event(QEvent *event)
         d->toggleViewAction->setChecked(true);
         QPoint parentTopLeft(0, 0);
         if (isWindow()) {
-            if (const QWindow *window = windowHandle())
-                parentTopLeft = window->screen()->availableVirtualGeometry().topLeft();
-            else
-                parentTopLeft = QGuiApplication::primaryScreen()->availableVirtualGeometry().topLeft();
+            const QScreen *screen = d->associatedScreen();
+            parentTopLeft = screen
+                ? screen->availableVirtualGeometry().topLeft()
+                : QGuiApplication::primaryScreen()->availableVirtualGeometry().topLeft();
         }
         emit visibilityChanged(geometry().right() >= parentTopLeft.x() && geometry().bottom() >= parentTopLeft.y());
 }
@@ -1556,8 +1558,10 @@ bool QDockWidget::event(QEvent *event)
             const QObjectList &siblings = win->children();
             onTop = siblings.count() > 0 && siblings.last() == (QObject*)this;
         }
+#if QT_CONFIG(tabbar)
         if (!isFloating() && layout != 0 && onTop)
             layout->raise(this);
+#endif
         break;
     }
     case QEvent::WindowActivate:
@@ -1590,7 +1594,7 @@ bool QDockWidget::event(QEvent *event)
             // This is a workaround for loosing the mouse on Vista.
             QPoint pos = QCursor::pos();
             QMouseEvent fake(QEvent::MouseMove, mapFromGlobal(pos), pos, Qt::NoButton,
-                             QApplication::mouseButtons(), QApplication::keyboardModifiers());
+                             QGuiApplication::mouseButtons(), QGuiApplication::keyboardModifiers());
             d->mouseMoveEvent(&fake);
         }
         break;
diff --git a/src/widgets/widgets/qeffects.cpp b/src/widgets/widgets/qeffects.cpp
index bcc8d7815d..9463641369 100644
--- a/src/widgets/widgets/qeffects.cpp
+++ b/src/widgets/widgets/qeffects.cpp
@@ -569,8 +569,8 @@ void qScrollEffect(QWidget* w, QEffects::DirFlags orient, int time)
     if (!w)
         return;
 
-    QApplication::sendPostedEvents(w, QEvent::Move);
-    QApplication::sendPostedEvents(w, QEvent::Resize);
+    QCoreApplication::sendPostedEvents(w, QEvent::Move);
+    QCoreApplication::sendPostedEvents(w, QEvent::Resize);
     Qt::WindowFlags flags = Qt::ToolTip;
 
     // those can be popups - they would steal the focus, but are disabled
@@ -591,8 +591,8 @@ void qFadeEffect(QWidget* w, int time)
     if (!w)
         return;
 
-    QApplication::sendPostedEvents(w, QEvent::Move);
-    QApplication::sendPostedEvents(w, QEvent::Resize);
+    QCoreApplication::sendPostedEvents(w, QEvent::Move);
+    QCoreApplication::sendPostedEvents(w, QEvent::Resize);
 
     Qt::WindowFlags flags = Qt::ToolTip;
 
diff --git a/src/widgets/widgets/qlineedit.cpp b/src/widgets/widgets/qlineedit.cpp
index 09b7687d8e..68e3de05bc 100644
--- a/src/widgets/widgets/qlineedit.cpp
+++ b/src/widgets/widgets/qlineedit.cpp
@@ -84,7 +84,7 @@
 #include "qkeysequence.h"
 #define ACCEL_KEY(k) ((!QCoreApplication::testAttribute(Qt::AA_DontShowIconsInMenus) \
                         && QGuiApplication::styleHints()->showShortcutsInContextMenus()) \
-                      && !qApp->d_func()->shortcutMap.hasShortcutForKeySequence(k) ? \
+                      && !QGuiApplicationPrivate::instance()->shortcutMap.hasShortcutForKeySequence(k) ? \
                       QLatin1Char('\t') + QKeySequence(k).toString(QKeySequence::NativeText) : QString())
 #else
 #define ACCEL_KEY(k) QString()
@@ -684,10 +684,10 @@ QSize QLineEdit::sizeHint() const
     ensurePolished();
     QFontMetrics fm(font());
     const int iconSize = style()->pixelMetric(QStyle::PM_SmallIconSize, 0, this);
-    int h = qMax(fm.height(), iconSize - 2) + 2*d->verticalMargin
+    int h = qMax(fm.height(), iconSize - 2) + 2 * QLineEditPrivate::verticalMargin
             + d->topTextMargin + d->bottomTextMargin
             + d->topmargin + d->bottommargin;
-    int w = fm.horizontalAdvance(QLatin1Char('x')) * 17 + 2*d->horizontalMargin
+    int w = fm.horizontalAdvance(QLatin1Char('x')) * 17 + 2 * QLineEditPrivate::horizontalMargin
             + d->effectiveLeftTextMargin() + d->effectiveRightTextMargin()
             + d->leftmargin + d->rightmargin; // "some"
     QStyleOptionFrame opt;
@@ -708,7 +708,7 @@ QSize QLineEdit::minimumSizeHint() const
     Q_D(const QLineEdit);
     ensurePolished();
     QFontMetrics fm = fontMetrics();
-    int h = fm.height() + qMax(2*d->verticalMargin, fm.leading())
+    int h = fm.height() + qMax(2 * QLineEditPrivate::verticalMargin, fm.leading())
             + d->topTextMargin + d->bottomTextMargin
             + d->topmargin + d->bottommargin;
     int w = fm.maxWidth()
@@ -1606,7 +1606,7 @@ void QLineEdit::mouseReleaseEvent(QMouseEvent* e)
     }
 #endif
 #ifndef QT_NO_CLIPBOARD
-    if (QApplication::clipboard()->supportsSelection()) {
+    if (QGuiApplication::clipboard()->supportsSelection()) {
         if (e->button() == Qt::LeftButton) {
             d->control->copy(QClipboard::Selection);
         } else if (!d->control->isReadOnly() && e->button() == Qt::MidButton) {
@@ -1960,17 +1960,18 @@ void QLineEdit::paintEvent(QPaintEvent *)
     Qt::Alignment va = QStyle::visualAlignment(d->control->layoutDirection(), QFlag(d->alignment));
     switch (va & Qt::AlignVertical_Mask) {
      case Qt::AlignBottom:
-         d->vscroll = r.y() + r.height() - fm.height() - d->verticalMargin;
+         d->vscroll = r.y() + r.height() - fm.height() - QLineEditPrivate::verticalMargin;
          break;
      case Qt::AlignTop:
-         d->vscroll = r.y() + d->verticalMargin;
+         d->vscroll = r.y() + QLineEditPrivate::verticalMargin;
          break;
      default:
          //center
          d->vscroll = r.y() + (r.height() - fm.height() + 1) / 2;
          break;
     }
-    QRect lineRect(r.x() + d->horizontalMargin, d->vscroll, r.width() - 2*d->horizontalMargin, fm.height());
+    QRect lineRect(r.x() + QLineEditPrivate::horizontalMargin, d->vscroll,
+                   r.width() - 2 * QLineEditPrivate::horizontalMargin, fm.height());
 
     if (d->shouldShowPlaceholderText()) {
         if (!d->placeholderText.isEmpty()) {
@@ -2206,7 +2207,7 @@ QMenu *QLineEdit::createStandardContextMenu()
 
     if (!isReadOnly()) {
         action = popup->addAction(QLineEdit::tr("&Paste") + ACCEL_KEY(QKeySequence::Paste));
-        action->setEnabled(!d->control->isReadOnly() && !QApplication::clipboard()->text().isEmpty());
+        action->setEnabled(!d->control->isReadOnly() && !QGuiApplication::clipboard()->text().isEmpty());
         setActionIcon(action, QStringLiteral("edit-paste"));
         connect(action, SIGNAL(triggered()), SLOT(paste()));
     }
diff --git a/src/widgets/widgets/qlineedit_p.cpp b/src/widgets/widgets/qlineedit_p.cpp
index 21e70db0ac..7d580e50a5 100644
--- a/src/widgets/widgets/qlineedit_p.cpp
+++ b/src/widgets/widgets/qlineedit_p.cpp
@@ -355,9 +355,7 @@ QLineEditPrivate *QLineEditIconButton::lineEditPrivate() const
 void QLineEditIconButton::paintEvent(QPaintEvent *)
 {
     QPainter painter(this);
-    QWindow *window = nullptr;
-    if (const QWidget *nativeParent = nativeParentWidget())
-        window = nativeParent->windowHandle();
+    QWindow *window = qt_widget_private(this)->windowHandle(QWidgetPrivate::WindowHandleMode::Closest);
     QIcon::Mode state = QIcon::Disabled;
     if (isEnabled())
         state = isDown() ? QIcon::Active : QIcon::Normal;
diff --git a/src/widgets/widgets/qmainwindow.cpp b/src/widgets/widgets/qmainwindow.cpp
index 9c4c46f2d6..16ed699137 100644
--- a/src/widgets/widgets/qmainwindow.cpp
+++ b/src/widgets/widgets/qmainwindow.cpp
@@ -1138,6 +1138,7 @@ void QMainWindow::splitDockWidget(QDockWidget *after, QDockWidget *dockwidget,
     d_func()->layout->splitDockWidget(after, dockwidget, orientation);
 }
 
+#if QT_CONFIG(tabbar)
 /*!
     \fn void QMainWindow::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
 
@@ -1164,9 +1165,6 @@ void QMainWindow::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
 QList<QDockWidget*> QMainWindow::tabifiedDockWidgets(QDockWidget *dockwidget) const
 {
     QList<QDockWidget*> ret;
-#if !QT_CONFIG(tabbar)
-    Q_UNUSED(dockwidget);
-#else
     const QDockAreaLayoutInfo *info = d_func()->layout->layoutState.dockAreaLayout.info(dockwidget);
     if (info && info->tabbed && info->tabBar) {
         for(int i = 0; i < info->item_list.count(); ++i) {
@@ -1180,9 +1178,9 @@ QList<QDockWidget*> QMainWindow::tabifiedDockWidgets(QDockWidget *dockwidget) co
             }
         }
     }
-#endif
     return ret;
 }
+#endif // QT_CONFIG(tabbar)
 
 
 /*!
diff --git a/src/widgets/widgets/qmainwindow.h b/src/widgets/widgets/qmainwindow.h
index 85e3f87d77..c69451fa3e 100644
--- a/src/widgets/widgets/qmainwindow.h
+++ b/src/widgets/widgets/qmainwindow.h
@@ -171,8 +171,10 @@ public:
                        Qt::Orientation orientation);
     void splitDockWidget(QDockWidget *after, QDockWidget *dockwidget,
                          Qt::Orientation orientation);
+#if QT_CONFIG(tabbar)
     void tabifyDockWidget(QDockWidget *first, QDockWidget *second);
     QList<QDockWidget*> tabifiedDockWidgets(QDockWidget *dockwidget) const;
+#endif
     void removeDockWidget(QDockWidget *dockwidget);
     bool restoreDockWidget(QDockWidget *dockwidget);
 
diff --git a/src/widgets/widgets/qmainwindowlayout.cpp b/src/widgets/widgets/qmainwindowlayout.cpp
index f54835f23b..0fb3a86cf8 100644
--- a/src/widgets/widgets/qmainwindowlayout.cpp
+++ b/src/widgets/widgets/qmainwindowlayout.cpp
@@ -292,25 +292,31 @@ bool QDockWidgetGroupWindow::event(QEvent *e)
 
     switch (e->type()) {
     case QEvent::Close:
+#if QT_CONFIG(tabbar)
         // Forward the close to the QDockWidget just as if its close button was pressed
         if (QDockWidget *dw = activeTabbedDockWidget()) {
             e->ignore();
             dw->close();
             adjustFlags();
         }
+#endif
         return true;
     case QEvent::Move:
+#if QT_CONFIG(tabbar)
         // Let QDockWidgetPrivate::moseEvent handle the dragging
         if (QDockWidget *dw = activeTabbedDockWidget())
             static_cast<QDockWidgetPrivate *>(QObjectPrivate::get(dw))->moveEvent(static_cast<QMoveEvent*>(e));
+#endif
         return true;
     case QEvent::NonClientAreaMouseMove:
     case QEvent::NonClientAreaMouseButtonPress:
     case QEvent::NonClientAreaMouseButtonRelease:
     case QEvent::NonClientAreaMouseButtonDblClick:
+#if QT_CONFIG(tabbar)
         // Let the QDockWidgetPrivate of the currently visible dock widget handle the drag and drop
         if (QDockWidget *dw = activeTabbedDockWidget())
             static_cast<QDockWidgetPrivate *>(QObjectPrivate::get(dw))->nonClientAreaMouseEvent(static_cast<QMouseEvent*>(e));
+#endif
         return true;
     case QEvent::ChildAdded:
         if (qobject_cast<QDockWidget *>(static_cast<QChildEvent*>(e)->child()))
@@ -347,6 +353,7 @@ QDockAreaLayoutInfo *QDockWidgetGroupWindow::layoutInfo() const
     return static_cast<QDockWidgetGroupLayout *>(layout())->dockAreaLayoutInfo();
 }
 
+#if QT_CONFIG(tabbar)
 /*! \internal
     If this is a floating tab bar returns the currently the QDockWidgetGroupWindow that contains
     tab, otherwise, return nullptr;
@@ -383,7 +390,6 @@ const QDockAreaLayoutInfo *QDockWidgetGroupWindow::tabLayoutInfo() const
 QDockWidget *QDockWidgetGroupWindow::activeTabbedDockWidget() const
 {
     QDockWidget *dw = nullptr;
-#if QT_CONFIG(tabbar)
     const QDockAreaLayoutInfo *info = tabLayoutInfo();
     if (!info)
         return nullptr;
@@ -405,9 +411,9 @@ QDockWidget *QDockWidgetGroupWindow::activeTabbedDockWidget() const
             dw = qobject_cast<QDockWidget *>(item.widgetItem->widget());
         }
     }
-#endif
     return dw;
 }
+#endif // QT_CONFIG(tabbar)
 
 /*! \internal
     Destroy or hide this window if there is no more QDockWidget in it.
@@ -461,7 +467,11 @@ void QDockWidgetGroupWindow::adjustFlags()
     Qt::WindowFlags oldFlags = windowFlags();
     Qt::WindowFlags flags = oldFlags;
 
+#if QT_CONFIG(tabbar)
     QDockWidget *top = activeTabbedDockWidget();
+#else
+    QDockWidget *top = nullptr;
+#endif
     if (!top) { // nested tabs, show window decoration
         flags =
             ((oldFlags & ~Qt::FramelessWindowHint) | Qt::CustomizeWindowHint | Qt::WindowTitleHint);
@@ -507,6 +517,7 @@ void QDockWidgetGroupWindow::adjustFlags()
 
 bool QDockWidgetGroupWindow::hasNativeDecos() const
 {
+#if QT_CONFIG(tabbar)
     QDockWidget *dw = activeTabbedDockWidget();
     if (!dw) // We have a group of nested QDockWidgets (not just floating tabs)
         return true;
@@ -515,6 +526,9 @@ bool QDockWidgetGroupWindow::hasNativeDecos() const
         return false;
 
     return dw->titleBarWidget() == nullptr;
+#else
+    return true;
+#endif
 }
 
 /*
@@ -531,16 +545,18 @@ bool QDockWidgetGroupWindow::hover(QLayoutItem *widgetItem, const QPoint &mouseP
         savedState = *layoutInfo();
 
     QMainWindow::DockOptions opts = static_cast<QMainWindow *>(parentWidget())->dockOptions();
+    QDockAreaLayoutInfo newState = savedState;
     bool nestingEnabled =
         (opts & QMainWindow::AllowNestedDocks) && !(opts & QMainWindow::ForceTabbedDocks);
     QDockAreaLayoutInfo::TabMode tabMode =
+#if !QT_CONFIG(tabbar)
+        QDockAreaLayoutInfo::NoTabs;
+#else
         nestingEnabled ? QDockAreaLayoutInfo::AllowTabs : QDockAreaLayoutInfo::ForceTabs;
     if (auto group = qobject_cast<QDockWidgetGroupWindow *>(widgetItem->widget())) {
         if (!group->tabLayoutInfo())
             tabMode = QDockAreaLayoutInfo::NoTabs;
     }
-
-    QDockAreaLayoutInfo newState = savedState;
     if (newState.tabbed) {
         // insertion into a top-level tab
         newState.item_list = { QDockAreaLayoutItem(new QDockAreaLayoutInfo(newState)) };
@@ -548,6 +564,7 @@ bool QDockWidgetGroupWindow::hover(QLayoutItem *widgetItem, const QPoint &mouseP
         newState.tabbed = false;
         newState.tabBar = nullptr;
     }
+#endif
 
     auto newGapPos = newState.gapIndex(mousePos, nestingEnabled, tabMode);
     Q_ASSERT(!newGapPos.isEmpty());
@@ -1498,14 +1515,6 @@ void QMainWindowLayout::addDockWidget(Qt::DockWidgetArea area,
     invalidate();
 }
 
-void QMainWindowLayout::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
-{
-    addChildWidget(second);
-    layoutState.dockAreaLayout.tabifyDockWidget(first, second);
-    emit second->dockLocationChanged(dockWidgetArea(first));
-    invalidate();
-}
-
 bool QMainWindowLayout::restoreDockWidget(QDockWidget *dockwidget)
 {
     addChildWidget(dockwidget);
@@ -1517,6 +1526,14 @@ bool QMainWindowLayout::restoreDockWidget(QDockWidget *dockwidget)
 }
 
 #if QT_CONFIG(tabbar)
+void QMainWindowLayout::tabifyDockWidget(QDockWidget *first, QDockWidget *second)
+{
+    addChildWidget(second);
+    layoutState.dockAreaLayout.tabifyDockWidget(first, second);
+    emit second->dockLocationChanged(dockWidgetArea(first));
+    invalidate();
+}
+
 bool QMainWindowLayout::documentMode() const
 {
     return _documentMode;
@@ -1535,20 +1552,15 @@ void QMainWindowLayout::setDocumentMode(bool enabled)
     for (QTabBar *bar : qAsConst(unusedTabBars))
         bar->setDocumentMode(_documentMode);
 }
-#endif // QT_CONFIG(tabbar)
 
 void QMainWindowLayout::setVerticalTabsEnabled(bool enabled)
 {
-#if !QT_CONFIG(tabbar)
-    Q_UNUSED(enabled);
-#else
     if (verticalTabsEnabled == enabled)
         return;
 
     verticalTabsEnabled = enabled;
 
     updateTabBarShapes();
-#endif // QT_CONFIG(tabbar)
 }
 
 #if QT_CONFIG(tabwidget)
@@ -1609,7 +1621,6 @@ static inline QTabBar::Shape tabBarShapeFrom(QTabWidget::TabShape shape, QTabWid
 }
 #endif // QT_CONFIG(tabwidget)
 
-#if QT_CONFIG(tabbar)
 void QMainWindowLayout::updateTabBarShapes()
 {
 #if QT_CONFIG(tabwidget)
@@ -1851,19 +1862,17 @@ void QMainWindowLayout::tabMoved(int from, int to)
 
     info->moveTab(from, to);
 }
-#endif // QT_CONFIG(tabbar)
 
 void QMainWindowLayout::raise(QDockWidget *widget)
 {
-#if QT_CONFIG(tabbar)
     QDockAreaLayoutInfo *info = dockInfo(widget);
     if (info == 0)
         return;
     if (!info->tabbed)
         return;
     info->setCurrentTab(widget);
-#endif
 }
+#endif // QT_CONFIG(tabbar)
 
 #endif // QT_CONFIG(dockwidget)
 
@@ -2329,7 +2338,7 @@ void QMainWindowLayout::setDockOptions(QMainWindow::DockOptions opts)
 
     dockOptions = opts;
 
-#if QT_CONFIG(dockwidget)
+#if QT_CONFIG(dockwidget) && QT_CONFIG(tabbar)
     setVerticalTabsEnabled(opts & QMainWindow::VerticalTabs);
 #endif
 
@@ -2413,7 +2422,7 @@ static bool unplugGroup(QMainWindowLayout *layout, QLayoutItem **item,
  */
 QLayoutItem *QMainWindowLayout::unplug(QWidget *widget, bool group)
 {
-#if QT_CONFIG(dockwidget) && QT_CONFIG(tabbar)
+#if QT_CONFIG(dockwidget) && QT_CONFIG(tabwidget)
     auto *groupWindow = qobject_cast<const QDockWidgetGroupWindow *>(widget->parentWidget());
     if (!widget->isWindow() && groupWindow) {
         if (group && groupWindow->tabLayoutInfo()) {
@@ -2525,10 +2534,10 @@ void QMainWindowLayout::updateGapIndicator()
 #endif // QT_CONFIG(rubberband)
 }
 
+#if QT_CONFIG(dockwidget) && QT_CONFIG(tabwidget)
 static QTabBar::Shape tabwidgetPositionToTabBarShape(QWidget *w)
 {
     QTabBar::Shape result = QTabBar::RoundedSouth;
-#if QT_CONFIG(tabwidget)
     if (qobject_cast<QDockWidget *>(w)) {
         switch (static_cast<QDockWidgetPrivate *>(qt_widget_private(w))->tabPosition) {
         case QTabWidget::North:
@@ -2545,9 +2554,9 @@ static QTabBar::Shape tabwidgetPositionToTabBarShape(QWidget *w)
             break;
         }
     }
-#endif // tabwidget
     return result;
 }
+#endif // QT_CONFIG(dockwidget) && QT_CONFIG(tabwidget)
 
 void QMainWindowLayout::hover(QLayoutItem *widgetItem, const QPoint &mousePos)
 {
@@ -2584,13 +2593,14 @@ void QMainWindowLayout::hover(QLayoutItem *widgetItem, const QPoint &mousePos)
             }
         }
         for (QWidget *w : candidates) {
-            QWindow *handle1 = widget->windowHandle();
-            QWindow *handle2 = w->windowHandle();
-            if (handle1 && handle2 && handle1->screen() != handle2->screen())
+            const QScreen *screen1 = qt_widget_private(widget)->associatedScreen();
+            const QScreen *screen2 = qt_widget_private(w)->associatedScreen();
+            if (screen1 && screen2 && screen1 != screen2)
                 continue;
             if (!w->geometry().contains(mousePos))
                 continue;
 
+#if QT_CONFIG(tabwidget)
             if (auto dropTo = qobject_cast<QDockWidget *>(w)) {
                 // dropping to a normal widget, we mutate it in a QDockWidgetGroupWindow with two
                 // tabs
@@ -2612,6 +2622,7 @@ void QMainWindowLayout::hover(QLayoutItem *widgetItem, const QPoint &mousePos)
                 w = floatingTabs;
                 widget->raise(); // raise, as our newly created drop target is now on top
             }
+#endif
             Q_ASSERT(qobject_cast<QDockWidgetGroupWindow *>(w));
             auto group = static_cast<QDockWidgetGroupWindow *>(w);
             if (group->hover(widgetItem, group->mapFromGlobal(mousePos))) {
diff --git a/src/widgets/widgets/qmainwindowlayout_p.h b/src/widgets/widgets/qmainwindowlayout_p.h
index 7cdb8ead2f..967b713096 100644
--- a/src/widgets/widgets/qmainwindowlayout_p.h
+++ b/src/widgets/widgets/qmainwindowlayout_p.h
@@ -337,8 +337,10 @@ public:
     explicit QDockWidgetGroupWindow(QWidget* parent = nullptr, Qt::WindowFlags f = nullptr)
         : QWidget(parent, f) {}
     QDockAreaLayoutInfo *layoutInfo() const;
+#if QT_CONFIG(tabbar)
     const QDockAreaLayoutInfo *tabLayoutInfo() const;
     QDockWidget *activeTabbedDockWidget() const;
+#endif
     void destroyOrHideIfEmpty();
     void adjustFlags();
     bool hasNativeDecos() const;
@@ -494,13 +496,13 @@ public:
     void splitDockWidget(QDockWidget *after,
                          QDockWidget *dockwidget,
                          Qt::Orientation orientation);
-    void tabifyDockWidget(QDockWidget *first, QDockWidget *second);
     Qt::DockWidgetArea dockWidgetArea(QWidget* widget) const;
+    bool restoreDockWidget(QDockWidget *dockwidget);
+#if QT_CONFIG(tabbar)
+    void tabifyDockWidget(QDockWidget *first, QDockWidget *second);
     void raise(QDockWidget *widget);
     void setVerticalTabsEnabled(bool enabled);
-    bool restoreDockWidget(QDockWidget *dockwidget);
 
-#if QT_CONFIG(tabbar)
     QDockAreaLayoutInfo *dockInfo(QWidget *w);
     bool _documentMode;
     bool documentMode() const;
diff --git a/src/widgets/widgets/qmdiarea.cpp b/src/widgets/widgets/qmdiarea.cpp
index fe3d1663a8..c7b7e5bf97 100644
--- a/src/widgets/widgets/qmdiarea.cpp
+++ b/src/widgets/widgets/qmdiarea.cpp
@@ -2525,7 +2525,7 @@ bool QMdiArea::event(QEvent *event)
     case QEvent::WindowIconChange:
         foreach (QMdiSubWindow *window, d->childWindows) {
             if (sanityCheck(window, "QMdiArea::WindowIconChange"))
-                QApplication::sendEvent(window, event);
+                QCoreApplication::sendEvent(window, event);
         }
         break;
     case QEvent::Hide:
diff --git a/src/widgets/widgets/qmdisubwindow.cpp b/src/widgets/widgets/qmdisubwindow.cpp
index e25bc6de7a..474cce983c 100644
--- a/src/widgets/widgets/qmdisubwindow.cpp
+++ b/src/widgets/widgets/qmdisubwindow.cpp
@@ -1826,7 +1826,7 @@ void QMdiSubWindowPrivate::showButtonsInMenuBar(QMenuBar *menuBar)
         // Make sure topLevelWindow->contentsRect returns correct geometry.
         // topLevelWidget->updateGeoemtry will not do the trick here since it will post the event.
         QEvent event(QEvent::LayoutRequest);
-        QApplication::sendEvent(topLevelWindow, &event);
+        QCoreApplication::sendEvent(topLevelWindow, &event);
     }
 }
 
@@ -1936,7 +1936,7 @@ QPalette QMdiSubWindowPrivate::desktopPalette() const
 #ifndef COLOR_GRADIENTINACTIVECAPTION
 #define COLOR_GRADIENTINACTIVECAPTION 28
 #endif
-    if (QApplication::desktopSettingsAware()) {
+    if (QGuiApplication::desktopSettingsAware()) {
         newPalette.setColor(QPalette::Active, QPalette::Highlight,
                             colorref2qrgb(GetSysColor(COLOR_ACTIVECAPTION)));
         newPalette.setColor(QPalette::Inactive, QPalette::Highlight,
@@ -1986,7 +1986,7 @@ void QMdiSubWindowPrivate::updateActions()
     for (int i = 0; i < NumWindowStateActions; ++i)
         setVisible(WindowStateAction(i), false);
 
-#ifdef Q_OS_MACOS
+#if defined(Q_OS_MACOS) && QT_CONFIG(action)
     if (q_func()->style()->inherits("QMacStyle"))
         for (int i = 0; i < NumWindowStateActions; ++i)
             if (QAction *action = actions[i])
@@ -3050,7 +3050,7 @@ void QMdiSubWindow::closeEvent(QCloseEvent *closeEvent)
     d->setActive(false);
     if (parentWidget() && testAttribute(Qt::WA_DeleteOnClose)) {
         QChildEvent childRemoved(QEvent::ChildRemoved, this);
-        QApplication::sendEvent(parentWidget(), &childRemoved);
+        QCoreApplication::sendEvent(parentWidget(), &childRemoved);
     }
     closeEvent->accept();
 }
@@ -3141,8 +3141,6 @@ void QMdiSubWindow::paintEvent(QPaintEvent *paintEvent)
     }
 
     Q_D(QMdiSubWindow);
-    if (isMaximized() && !d->drawTitleBarWhenMaximized())
-        return;
 
     if (d->resizeTimerId != -1) {
         // Only update the style option rect and the window title.
@@ -3162,6 +3160,17 @@ void QMdiSubWindow::paintEvent(QPaintEvent *paintEvent)
     }
 
     QStylePainter painter(this);
+    QStyleOptionFrame frameOptions;
+    frameOptions.initFrom(this);
+    frameOptions.state.setFlag(QStyle::State_Active, d->isActive);
+    if (isMaximized() && !d->drawTitleBarWhenMaximized()) {
+        if (!autoFillBackground() && (!widget() || !qt_widget_private(widget())->isOpaque)) {
+            // make sure we paint all pixels of a maximized QMdiSubWindow if no-one else does
+            painter.drawPrimitive(QStyle::PE_FrameWindow, frameOptions);
+        }
+        return;
+    }
+
     if (!d->windowTitle.isEmpty())
         painter.setFont(d->font);
     painter.drawComplexControl(QStyle::CC_TitleBar, d->cachedStyleOptions);
@@ -3169,10 +3178,7 @@ void QMdiSubWindow::paintEvent(QPaintEvent *paintEvent)
     if (isMinimized() && !d->hasBorder(d->cachedStyleOptions))
         return;
 
-    QStyleOptionFrame frameOptions;
-    frameOptions.initFrom(this);
     frameOptions.lineWidth = style()->pixelMetric(QStyle::PM_MdiSubWindowFrameWidth, 0, this);
-    frameOptions.state.setFlag(QStyle::State_Active, d->isActive);
 
     // ### Ensure that we do not require setting the cliprect for 4.4
     if (!isMinimized() && !d->hasBorder(d->cachedStyleOptions))
diff --git a/src/widgets/widgets/qmenu.cpp b/src/widgets/widgets/qmenu.cpp
index 287be3e272..72653b377d 100644
--- a/src/widgets/widgets/qmenu.cpp
+++ b/src/widgets/widgets/qmenu.cpp
@@ -264,7 +264,7 @@ void QMenuPrivate::copyActionToPlatformItem(const QAction *action, QPlatformMenu
             item->setIconSize(w->style()->pixelMetric(QStyle::PM_SmallIconSize, &opt, w));
         } else {
             QStyleOption opt;
-            item->setIconSize(qApp->style()->pixelMetric(QStyle::PM_SmallIconSize, &opt, 0));
+            item->setIconSize(QApplication::style()->pixelMetric(QStyle::PM_SmallIconSize, &opt, 0));
         }
     } else {
         item->setIcon(QIcon());
@@ -907,7 +907,7 @@ void QMenuPrivate::updateLayoutDirection()
         else if (QWidget *w = q->parentWidget())
             setLayoutDirection_helper(w->layoutDirection());
         else
-            setLayoutDirection_helper(QApplication::layoutDirection());
+            setLayoutDirection_helper(QGuiApplication::layoutDirection());
     }
 }
 
@@ -1335,7 +1335,7 @@ bool QMenuPrivate::mouseEventTaken(QMouseEvent *e)
             if (e->type() != QEvent::MouseButtonRelease || mouseDown == caused) {
                 QMouseEvent new_e(e->type(), cpos, caused->mapTo(caused->topLevelWidget(), cpos), e->screenPos(),
                                   e->button(), e->buttons(), e->modifiers(), e->source());
-                QApplication::sendEvent(caused, &new_e);
+                QCoreApplication::sendEvent(caused, &new_e);
                 return true;
             }
         }
@@ -1543,7 +1543,7 @@ void QMenu::initStyleOption(QStyleOptionMenuItem *option, const QAction *action)
 
     if (d->currentAction && d->currentAction == action && !d->currentAction->isSeparator()) {
         option->state |= QStyle::State_Selected
-                     | (d->mouseDown ? QStyle::State_Sunken : QStyle::State_None);
+                     | (QMenuPrivate::mouseDown ? QStyle::State_Sunken : QStyle::State_None);
     }
 
     option->menuHasCheckableItems = d->hasCheckableItems;
@@ -2331,8 +2331,18 @@ void QMenu::popup(const QPoint &p, QAction *atAction)
     d->updateLayoutDirection();
 
     // Ensure that we get correct sizeHints by placing this window on the correct screen.
-    if (d->setScreenForPoint(p))
+    // However if the QMenu was constructed with a QDesktopScreenWidget as its parent,
+    // then initialScreenIndex was set, so we should respect that for the lifetime of this menu.
+    // Use d->popupScreen to remember, because initialScreenIndex will be reset after the first showing.
+    const int screenIndex = d->topData()->initialScreenIndex;
+    if (screenIndex >= 0)
+        d->popupScreen = screenIndex;
+    if (auto s = QGuiApplication::screens().value(d->popupScreen)) {
+        if (d->setScreen(s))
+            d->itemsDirty = true;
+    } else if (d->setScreenForPoint(p)) {
         d->itemsDirty = true;
+    }
 
     const bool contextMenu = d->isContextMenu();
     if (d->lastContextMenu != contextMenu) {
@@ -2352,7 +2362,7 @@ void QMenu::popup(const QPoint &p, QAction *atAction)
 
     QRect screen;
 #if QT_CONFIG(graphicsview)
-    bool isEmbedded = !bypassGraphicsProxyWidget(this) && d->nearestGraphicsProxyWidget(this);
+    bool isEmbedded = !bypassGraphicsProxyWidget(this) && QMenuPrivate::nearestGraphicsProxyWidget(this);
     if (isEmbedded)
         screen = d->popupGeometry();
     else
@@ -2688,8 +2698,8 @@ void QMenu::hideEvent(QHideEvent *)
     if (QMenuBar *mb = qobject_cast<QMenuBar*>(d->causedPopup.widget))
         mb->d_func()->setCurrentAction(0);
 #endif
-    if (d->mouseDown == this)
-        d->mouseDown = 0;
+    if (QMenuPrivate::mouseDown == this)
+        QMenuPrivate::mouseDown = nullptr;
     d->hasHadMouse = false;
     if (d->activeMenu)
         d->hideMenu(d->activeMenu);
@@ -2864,7 +2874,7 @@ void QMenu::mousePressEvent(QMouseEvent *e)
         d->hideUpToMenuBar();
         return;
     }
-    d->mouseDown = this;
+    QMenuPrivate::mouseDown = this;
 
     QAction *action = d->actionAt(e->pos());
     d->setCurrentAction(action, 20);
@@ -2879,12 +2889,12 @@ void QMenu::mouseReleaseEvent(QMouseEvent *e)
     Q_D(QMenu);
     if (d->aboutToHide || d->mouseEventTaken(e))
         return;
-    if(d->mouseDown != this) {
-        d->mouseDown = 0;
+    if (QMenuPrivate::mouseDown != this) {
+        QMenuPrivate::mouseDown = nullptr;
         return;
     }
 
-    d->mouseDown = 0;
+    QMenuPrivate::mouseDown = nullptr;
     d->setSyncAction();
     QAction *action = d->actionAt(e->pos());
 
@@ -2985,7 +2995,7 @@ QMenu::event(QEvent *e)
         d->updateActionRects();
         break; }
     case QEvent::Show:
-        d->mouseDown = 0;
+        QMenuPrivate::mouseDown = nullptr;
         d->updateActionRects();
         d->sloppyState.reset();
         if (d->currentAction)
@@ -3375,7 +3385,7 @@ void QMenu::keyPressEvent(QKeyEvent *e)
 #if QT_CONFIG(menubar)
             if (QMenuBar *mb = qobject_cast<QMenuBar*>(d->topCausedWidget())) {
                 QAction *oldAct = mb->d_func()->currentAction;
-                QApplication::sendEvent(mb, e);
+                QCoreApplication::sendEvent(mb, e);
                 if (mb->d_func()->currentAction != oldAct)
                     key_consumed = true;
             }
@@ -3418,7 +3428,7 @@ void QMenu::mouseMoveEvent(QMouseEvent *e)
     }
 
     if (e->buttons())
-        d->mouseDown = this;
+        QMenuPrivate::mouseDown = this;
 
     if (d->activeMenu)
         d->activeMenu->d_func()->setCurrentAction(0);
@@ -3583,7 +3593,7 @@ void QMenu::internalDelayedPopup()
 
     QRect screen;
 #if QT_CONFIG(graphicsview)
-    bool isEmbedded = !bypassGraphicsProxyWidget(this) && d->nearestGraphicsProxyWidget(this);
+    bool isEmbedded = !bypassGraphicsProxyWidget(this) && QMenuPrivate::nearestGraphicsProxyWidget(this);
     if (isEmbedded)
         screen = d->popupGeometry();
     else
diff --git a/src/widgets/widgets/qmenu_p.h b/src/widgets/widgets/qmenu_p.h
index ef152cd71b..efbbc099a1 100644
--- a/src/widgets/widgets/qmenu_p.h
+++ b/src/widgets/widgets/qmenu_p.h
@@ -515,6 +515,8 @@ public:
     bool tearoffHighlighted : 1;
     //menu fading/scrolling effects
     bool doChildEffects : 1;
+
+    int popupScreen = -1;
 };
 
 QT_END_NAMESPACE
diff --git a/src/widgets/widgets/qmenubar.cpp b/src/widgets/widgets/qmenubar.cpp
index a53d7841f4..3d31a3b73a 100644
--- a/src/widgets/widgets/qmenubar.cpp
+++ b/src/widgets/widgets/qmenubar.cpp
@@ -68,6 +68,7 @@
 
 #include "qmenu_p.h"
 #include "qmenubar_p.h"
+#include <private/qscreen_p.h>
 #include "qdebug.h"
 
 QT_BEGIN_NAMESPACE
@@ -322,11 +323,18 @@ void QMenuBarPrivate::popupAction(QAction *action, bool activateFirst)
         QRect adjustedActionRect = actionRect(action);
         QPoint pos(q->mapToGlobal(QPoint(adjustedActionRect.left(), adjustedActionRect.bottom() + 1)));
         QSize popup_size = activeMenu->sizeHint();
-
         //we put the popup menu on the screen containing the bottom-center of the action rect
-        QRect screenRect = QDesktopWidgetPrivate::screenGeometry(pos + QPoint(adjustedActionRect.width() / 2, 0));
+        QScreen *popupScreen = q->window()->windowHandle()->screen();
+        QPoint bottomMiddlePos = pos + QPoint(adjustedActionRect.width() / 2, 0);
+        const auto &siblings = popupScreen->virtualSiblings();
+        for (QScreen *sibling : siblings) {
+            if (sibling->geometry().contains(bottomMiddlePos)) {
+                popupScreen = sibling;
+                break;
+            }
+        }
+        QRect screenRect = popupScreen->geometry();
         pos = QPoint(qMax(pos.x(), screenRect.x()), qMax(pos.y(), screenRect.y()));
-
         const bool fitUp = (pos.y() - popup_size.height() >= screenRect.top());
         const bool fitDown = (pos.y() + popup_size.height() <= screenRect.bottom());
         const bool rtl = q->isRightToLeft();
@@ -352,6 +360,7 @@ void QMenuBarPrivate::popupAction(QAction *action, bool activateFirst)
 
         if(!defaultPopDown || (fitUp && !fitDown))
             pos.setY(qMax(screenRect.y(), q->mapToGlobal(QPoint(0, adjustedActionRect.top()-popup_size.height())).y()));
+        QMenuPrivate::get(activeMenu)->topData()->initialScreenIndex = QGuiApplication::screens().indexOf(popupScreen);
         activeMenu->popup(pos);
         if(activateFirst)
             activeMenu->d_func()->setFirstActionActive();
@@ -395,7 +404,7 @@ void QMenuBarPrivate::setCurrentAction(QAction *action, bool popup, bool activat
     }  else if (previousAction) {
         QString empty;
         QStatusTipEvent tip(empty);
-        QApplication::sendEvent(q, &tip);
+        QCoreApplication::sendEvent(q, &tip);
 #endif
     }
     if (fw)
@@ -692,7 +701,7 @@ void QMenuBarPrivate::init()
     q->setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::Minimum);
     q->setAttribute(Qt::WA_CustomWhatsThis);
 
-    if (!QApplication::instance()->testAttribute(Qt::AA_DontUseNativeMenuBar))
+    if (!QCoreApplication::testAttribute(Qt::AA_DontUseNativeMenuBar))
         platformMenuBar = QGuiApplicationPrivate::platformTheme()->createPlatformMenuBar();
 
     if (platformMenuBar)
diff --git a/src/widgets/widgets/qplaintextedit.cpp b/src/widgets/widgets/qplaintextedit.cpp
index bc1ff78de0..397304ec44 100644
--- a/src/widgets/widgets/qplaintextedit.cpp
+++ b/src/widgets/widgets/qplaintextedit.cpp
@@ -1588,7 +1588,7 @@ bool QPlainTextEdit::event(QEvent *e)
                 d->originalOffsetY = vBar->value();
             QPointF offset = g->offset();
             if (!offset.isNull()) {
-                if (QApplication::isRightToLeft())
+                if (QGuiApplication::isRightToLeft())
                     offset.rx() *= -1;
                 // QPlainTextEdit scrolls by lines only in vertical direction
                 QFontMetrics fm(document()->defaultFont());
@@ -1957,6 +1957,7 @@ void QPlainTextEdit::paintEvent(QPaintEvent *e)
     }
 
     QAbstractTextDocumentLayout::PaintContext context = getPaintContext();
+    painter.setPen(context.palette.text().color());
 
     while (block.isValid()) {
 
@@ -2648,7 +2649,7 @@ void QPlainTextEdit::setReadOnly(bool ro)
     d->control->setTextInteractionFlags(flags);
     setAttribute(Qt::WA_InputMethodEnabled, shouldEnableInputMethod(this));
     QEvent event(QEvent::ReadOnlyChange);
-    QApplication::sendEvent(this, &event);
+    QCoreApplication::sendEvent(this, &event);
 }
 
 /*!
diff --git a/src/widgets/widgets/qspinbox.cpp b/src/widgets/widgets/qspinbox.cpp
index 97a3a12336..61ea81c892 100644
--- a/src/widgets/widgets/qspinbox.cpp
+++ b/src/widgets/widgets/qspinbox.cpp
@@ -384,7 +384,7 @@ void QSpinBox::setMinimum(int minimum)
 {
     Q_D(QSpinBox);
     const QVariant m(minimum);
-    d->setRange(m, (d->variantCompare(d->maximum, m) > 0 ? d->maximum : m));
+    d->setRange(m, (QSpinBoxPrivate::variantCompare(d->maximum, m) > 0 ? d->maximum : m));
 }
 
 /*!
@@ -412,7 +412,7 @@ void QSpinBox::setMaximum(int maximum)
 {
     Q_D(QSpinBox);
     const QVariant m(maximum);
-    d->setRange((d->variantCompare(d->minimum, m) < 0 ? d->minimum : m), m);
+    d->setRange((QSpinBoxPrivate::variantCompare(d->minimum, m) < 0 ? d->minimum : m), m);
 }
 
 /*!
@@ -864,7 +864,7 @@ void QDoubleSpinBox::setMinimum(double minimum)
     Q_D(QDoubleSpinBox);
     d->actualMin = minimum;
     const QVariant m(d->round(minimum));
-    d->setRange(m, (d->variantCompare(d->maximum, m) > 0 ? d->maximum : m));
+    d->setRange(m, (QDoubleSpinBoxPrivate::variantCompare(d->maximum, m) > 0 ? d->maximum : m));
 }
 
 /*!
@@ -895,7 +895,7 @@ void QDoubleSpinBox::setMaximum(double maximum)
     Q_D(QDoubleSpinBox);
     d->actualMax = maximum;
     const QVariant m(d->round(maximum));
-    d->setRange((d->variantCompare(d->minimum, m) < 0 ? d->minimum : m), m);
+    d->setRange((QDoubleSpinBoxPrivate::variantCompare(d->minimum, m) < 0 ? d->minimum : m), m);
 }
 
 /*!
diff --git a/src/widgets/widgets/qsplashscreen.cpp b/src/widgets/widgets/qsplashscreen.cpp
index bf6bf1c7c9..e39ef6d1cd 100644
--- a/src/widgets/widgets/qsplashscreen.cpp
+++ b/src/widgets/widgets/qsplashscreen.cpp
@@ -111,7 +111,7 @@ public:
    The user can hide the splash screen by clicking on it with the
    mouse. Since the splash screen is typically displayed before the
    event loop has started running, it is necessary to periodically
-   call QApplication::processEvents() to receive the mouse clicks.
+   call QCoreApplication::processEvents() to receive the mouse clicks.
 
    It is sometimes useful to update the splash screen with messages,
    for example, announcing connections established or modules loaded
@@ -170,13 +170,13 @@ void QSplashScreen::mousePressEvent(QMouseEvent *)
 
 /*!
     This overrides QWidget::repaint(). It differs from the standard repaint
-    function in that it also calls QApplication::processEvents() to ensure
+    function in that it also calls QCoreApplication::processEvents() to ensure
     the updates are displayed, even when there is no event loop present.
 */
 void QSplashScreen::repaint()
 {
     QWidget::repaint();
-    QApplication::processEvents();
+    QCoreApplication::processEvents();
 }
 
 /*!
diff --git a/src/widgets/widgets/qtabbar.cpp b/src/widgets/widgets/qtabbar.cpp
index b13f4da9d2..f6f56c12d1 100644
--- a/src/widgets/widgets/qtabbar.cpp
+++ b/src/widgets/widgets/qtabbar.cpp
@@ -843,7 +843,7 @@ void QTabBarPrivate::refresh()
     // be safe in case a subclass is also handling move with the tabs
     if (pressedIndex != -1
         && movable
-        && QApplication::mouseButtons() == Qt::NoButton) {
+        && QGuiApplication::mouseButtons() == Qt::NoButton) {
         moveTabFinished(pressedIndex);
         if (!validIndex(pressedIndex))
             pressedIndex = -1;
diff --git a/src/widgets/widgets/qtextbrowser.cpp b/src/widgets/widgets/qtextbrowser.cpp
index 8e06efc75e..7a77f86de2 100644
--- a/src/widgets/widgets/qtextbrowser.cpp
+++ b/src/widgets/widgets/qtextbrowser.cpp
@@ -57,7 +57,6 @@
 #endif
 #include <qtextobject.h>
 #include <qdesktopservices.h>
-#include <qmimedatabase.h>
 
 QT_BEGIN_NAMESPACE
 
@@ -86,6 +85,7 @@ public:
         int hpos;
         int vpos;
         int focusIndicatorPosition, focusIndicatorAnchor;
+        QTextDocument::ResourceType type = QTextDocument::UnknownResource;
     };
 
     HistoryEntry history(int i) const
@@ -122,6 +122,8 @@ public:
     bool openExternalLinks;
     bool openLinks;
 
+    QTextDocument::ResourceType currentType;
+
 #ifndef QT_NO_CURSOR
     QCursor oldCursor;
 #endif
@@ -137,7 +139,7 @@ public:
     void _q_activateAnchor(const QString &href);
     void _q_highlightLink(const QString &href);
 
-    void setSource(const QUrl &url);
+    void setSource(const QUrl &url, QTextDocument::ResourceType type);
 
     // re-imlemented from QTextEditPrivate
     virtual QUrl resolveUrl(const QUrl &url) const override;
@@ -274,7 +276,7 @@ void QTextBrowserPrivate::_q_highlightLink(const QString &anchor)
     }
 }
 
-void QTextBrowserPrivate::setSource(const QUrl &url)
+void QTextBrowserPrivate::setSource(const QUrl &url, QTextDocument::ResourceType type)
 {
     Q_Q(QTextBrowser);
 #ifndef QT_NO_CURSOR
@@ -291,14 +293,18 @@ void QTextBrowserPrivate::setSource(const QUrl &url)
     currentUrlWithoutFragment.setFragment(QString());
     QUrl newUrlWithoutFragment = currentURL.resolved(url);
     newUrlWithoutFragment.setFragment(QString());
-    QTextDocument::ResourceType type = QTextDocument::HtmlResource;
     QString fileName = url.fileName();
+    if (type == QTextDocument::UnknownResource) {
 #if QT_CONFIG(textmarkdownreader)
-    if (fileName.endsWith(QLatin1String(".md")) ||
-            fileName.endsWith(QLatin1String(".mkd")) ||
-            fileName.endsWith(QLatin1String(".markdown")))
-        type = QTextDocument::MarkdownResource;
+        if (fileName.endsWith(QLatin1String(".md")) ||
+                fileName.endsWith(QLatin1String(".mkd")) ||
+                fileName.endsWith(QLatin1String(".markdown")))
+            type = QTextDocument::MarkdownResource;
+        else
 #endif
+            type = QTextDocument::HtmlResource;
+    }
+    currentType = type;
 
     if (url.isValid()
         && (newUrlWithoutFragment != currentUrlWithoutFragment || forceLoadOnSourceChange)) {
@@ -306,13 +312,17 @@ void QTextBrowserPrivate::setSource(const QUrl &url)
         if (data.type() == QVariant::String) {
             txt = data.toString();
         } else if (data.type() == QVariant::ByteArray) {
+            if (type == QTextDocument::HtmlResource) {
 #if QT_CONFIG(textcodec)
-            QByteArray ba = data.toByteArray();
-            QTextCodec *codec = Qt::codecForHtml(ba);
-            txt = codec->toUnicode(ba);
+                QByteArray ba = data.toByteArray();
+                QTextCodec *codec = Qt::codecForHtml(ba);
+                txt = codec->toUnicode(ba);
 #else
-            txt = data.toString();
+                txt = data.toString();
 #endif
+            } else {
+                txt = QString::fromUtf8(data.toByteArray());
+            }
         }
         if (Q_UNLIKELY(txt.isEmpty()))
             qWarning("QTextBrowser: No document for %s", url.toString().toLatin1().constData());
@@ -574,6 +584,7 @@ QTextBrowserPrivate::HistoryEntry QTextBrowserPrivate::createHistoryEntry() cons
 {
     HistoryEntry entry;
     entry.url = q_func()->source();
+    entry.type = q_func()->sourceType();
     entry.title = q_func()->documentTitle();
     entry.hpos = hbar->value();
     entry.vpos = vbar->value();
@@ -590,7 +601,7 @@ QTextBrowserPrivate::HistoryEntry QTextBrowserPrivate::createHistoryEntry() cons
 
 void QTextBrowserPrivate::restoreHistoryEntry(const HistoryEntry &entry)
 {
-    setSource(entry.url);
+    setSource(entry.url, entry.type);
     hbar->setValue(entry.hpos);
     vbar->setValue(entry.vpos);
     if (entry.focusIndicatorAnchor != -1 && entry.focusIndicatorPosition != -1) {
@@ -732,7 +743,13 @@ QTextBrowser::~QTextBrowser()
     document is displayed as a popup rather than as new document in
     the browser window itself. Otherwise, the document is displayed
     normally in the text browser with the text set to the contents of
-    the named document with setHtml().
+    the named document with \l QTextDocument::setHtml() or
+    \l QTextDocument::setMarkdown(), depending on whether the filename ends
+    with any of the known Markdown file extensions.
+
+    If you would like to avoid automatic type detection
+    and specify the type explicitly, call setSource() rather than
+    setting this property.
 
     By default, this property contains an empty URL.
 */
@@ -746,6 +763,23 @@ QUrl QTextBrowser::source() const
 }
 
 /*!
+    \property QTextBrowser::sourceType
+    \brief the type of the displayed document
+
+    This is QTextDocument::UnknownResource if no document is displayed or if
+    the type of the source is unknown. Otherwise it holds the type that was
+    detected, or the type that was specified when setSource() was called.
+*/
+QTextDocument::ResourceType QTextBrowser::sourceType() const
+{
+    Q_D(const QTextBrowser);
+    if (d->stack.isEmpty())
+        return QTextDocument::UnknownResource;
+    else
+        return d->stack.top().type;
+}
+
+/*!
     \property QTextBrowser::searchPaths
     \brief the search paths used by the text browser to find supporting
     content
@@ -775,16 +809,46 @@ void QTextBrowser::reload()
     Q_D(QTextBrowser);
     QUrl s = d->currentURL;
     d->currentURL = QUrl();
-    setSource(s);
+    setSource(s, d->currentType);
 }
 
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
 void QTextBrowser::setSource(const QUrl &url)
 {
+    setSource(url, QTextDocument::UnknownResource);
+}
+#endif
+
+/*!
+    Attempts to load the document at the given \a url with the specified \a type.
+
+    If \a type is \l {QTextDocument::ResourceType::UnknownResource}{UnknownResource}
+    (the default), the document type will be detected: that is, if the url ends
+    with an extension of \c{.md}, \c{.mkd} or \c{.markdown}, the document will be
+    loaded via \l QTextDocument::setMarkdown(); otherwise it will be loaded via
+    \l QTextDocument::setHtml(). This detection can be bypassed by specifying
+    the \a type explicitly.
+*/
+void QTextBrowser::setSource(const QUrl &url, QTextDocument::ResourceType type)
+{
+    doSetSource(url, type);
+}
+
+#if QT_VERSION >= QT_VERSION_CHECK(6,0,0)
+/*!
+    Attempts to load the document at the given \a url with the specified \a type.
+
+    setSource() calls doSetSource.  In Qt 5, setSource(const QUrl &url) was virtual.
+    In Qt 6, doSetSource() is virtual instead, so that it can be overridden in subclasses.
+*/
+#endif
+void QTextBrowser::doSetSource(const QUrl &url, QTextDocument::ResourceType type)
+{
     Q_D(QTextBrowser);
 
     const QTextBrowserPrivate::HistoryEntry historyEntry = d->createHistoryEntry();
 
-    d->setSource(url);
+    d->setSource(url, type);
 
     if (!url.isValid())
         return;
@@ -798,6 +862,7 @@ void QTextBrowser::setSource(const QUrl &url)
 
     QTextBrowserPrivate::HistoryEntry entry;
     entry.url = url;
+    entry.type = d->currentType;
     entry.title = documentTitle();
     entry.hpos = 0;
     entry.vpos = 0;
diff --git a/src/widgets/widgets/qtextbrowser.h b/src/widgets/widgets/qtextbrowser.h
index ea81256f50..33e5b3980c 100644
--- a/src/widgets/widgets/qtextbrowser.h
+++ b/src/widgets/widgets/qtextbrowser.h
@@ -55,6 +55,7 @@ class Q_WIDGETS_EXPORT QTextBrowser : public QTextEdit
     Q_OBJECT
 
     Q_PROPERTY(QUrl source READ source WRITE setSource)
+    Q_PROPERTY(QTextDocument::ResourceType sourceType READ sourceType)
     Q_OVERRIDE(bool modified SCRIPTABLE false)
     Q_OVERRIDE(bool readOnly DESIGNABLE false SCRIPTABLE false)
     Q_OVERRIDE(bool undoRedoEnabled DESIGNABLE false SCRIPTABLE false)
@@ -67,6 +68,7 @@ public:
     virtual ~QTextBrowser();
 
     QUrl source() const;
+    QTextDocument::ResourceType sourceType() const;
 
     QStringList searchPaths() const;
     void setSearchPaths(const QStringList &paths);
@@ -88,7 +90,12 @@ public:
     void setOpenLinks(bool open);
 
 public Q_SLOTS:
+#if QT_VERSION < QT_VERSION_CHECK(6,0,0)
     virtual void setSource(const QUrl &name);
+    void setSource(const QUrl &name, QTextDocument::ResourceType type);
+#else
+    void setSource(const QUrl &name, QTextDocument::ResourceType type = QTextDocument::UnknownResource);
+#endif
     virtual void backward();
     virtual void forward();
     virtual void home();
@@ -112,6 +119,10 @@ protected:
     virtual void focusOutEvent(QFocusEvent *ev) override;
     virtual bool focusNextPrevChild(bool next) override;
     virtual void paintEvent(QPaintEvent *e) override;
+#if QT_VERSION >= QT_VERSION_CHECK(6,0,0)
+    virtual
+#endif
+    void doSetSource(const QUrl &name, QTextDocument::ResourceType type = QTextDocument::UnknownResource);
 
 private:
     Q_DISABLE_COPY(QTextBrowser)
diff --git a/src/widgets/widgets/qtextedit.cpp b/src/widgets/widgets/qtextedit.cpp
index 01f7c34f93..8599573e5a 100644
--- a/src/widgets/widgets/qtextedit.cpp
+++ b/src/widgets/widgets/qtextedit.cpp
@@ -167,7 +167,9 @@ void QTextEditPrivate::init(const QString &html)
     QObject::connect(control, SIGNAL(copyAvailable(bool)), q, SIGNAL(copyAvailable(bool)));
     QObject::connect(control, SIGNAL(selectionChanged()), q, SIGNAL(selectionChanged()));
     QObject::connect(control, SIGNAL(cursorPositionChanged()), q, SLOT(_q_cursorPositionChanged()));
+#if QT_CONFIG(cursor)
     QObject::connect(control, SIGNAL(blockMarkerHovered(QTextBlock)), q, SLOT(_q_hoveredBlockWithMarkerChanged(QTextBlock)));
+#endif
 
     QObject::connect(control, SIGNAL(textChanged()), q, SLOT(updateMicroFocus()));
 
@@ -230,6 +232,7 @@ void QTextEditPrivate::_q_cursorPositionChanged()
 #endif
 }
 
+#if QT_CONFIG(cursor)
 void QTextEditPrivate::_q_hoveredBlockWithMarkerChanged(const QTextBlock &block)
 {
     Q_Q(QTextEdit);
@@ -244,6 +247,7 @@ void QTextEditPrivate::_q_hoveredBlockWithMarkerChanged(const QTextBlock &block)
     }
     viewport->setCursor(cursor);
 }
+#endif
 
 void QTextEditPrivate::pageUpDown(QTextCursor::MoveOperation op, QTextCursor::MoveMode moveMode)
 {
@@ -2260,7 +2264,7 @@ void QTextEdit::setReadOnly(bool ro)
     d->control->setTextInteractionFlags(flags);
     setAttribute(Qt::WA_InputMethodEnabled, shouldEnableInputMethod(this));
     QEvent event(QEvent::ReadOnlyChange);
-    QApplication::sendEvent(this, &event);
+    QCoreApplication::sendEvent(this, &event);
 }
 
 /*!
diff --git a/src/widgets/widgets/qtextedit.h b/src/widgets/widgets/qtextedit.h
index 09ef44b7b2..5c8a3c7793 100644
--- a/src/widgets/widgets/qtextedit.h
+++ b/src/widgets/widgets/qtextedit.h
@@ -331,7 +331,9 @@ private:
     Q_PRIVATE_SLOT(d_func(), void _q_adjustScrollbars())
     Q_PRIVATE_SLOT(d_func(), void _q_ensureVisible(const QRectF &))
     Q_PRIVATE_SLOT(d_func(), void _q_cursorPositionChanged())
+#if QT_CONFIG(cursor)
     Q_PRIVATE_SLOT(d_func(), void _q_hoveredBlockWithMarkerChanged(const QTextBlock &))
+#endif
     friend class QTextEditControl;
     friend class QTextDocument;
     friend class QWidgetTextControl;
diff --git a/src/widgets/widgets/qtoolbar.cpp b/src/widgets/widgets/qtoolbar.cpp
index bcf5a40ae3..fcaafbc581 100644
--- a/src/widgets/widgets/qtoolbar.cpp
+++ b/src/widgets/widgets/qtoolbar.cpp
@@ -1172,7 +1172,7 @@ bool QToolBar::event(QEvent *event)
             // This is a workaround for loosing the mouse on Vista.
             QPoint pos = QCursor::pos();
             QMouseEvent fake(QEvent::MouseMove, mapFromGlobal(pos), pos, Qt::NoButton,
-                             QApplication::mouseButtons(), QApplication::keyboardModifiers());
+                             QGuiApplication::mouseButtons(), QGuiApplication::keyboardModifiers());
             d->mouseMoveEvent(&fake);
 #endif
         } else {
diff --git a/src/widgets/widgets/qwidgetlinecontrol.cpp b/src/widgets/widgets/qwidgetlinecontrol.cpp
index cf2d885b52..56dba1dd32 100644
--- a/src/widgets/widgets/qwidgetlinecontrol.cpp
+++ b/src/widgets/widgets/qwidgetlinecontrol.cpp
@@ -158,7 +158,7 @@ void QWidgetLineControl::copy(QClipboard::Mode mode) const
 {
     QString t = selectedText();
     if (!t.isEmpty() && m_echoMode == QLineEdit::Normal) {
-        QApplication::clipboard()->setText(t, mode);
+        QGuiApplication::clipboard()->setText(t, mode);
     }
 }
 
@@ -172,7 +172,7 @@ void QWidgetLineControl::copy(QClipboard::Mode mode) const
 */
 void QWidgetLineControl::paste(QClipboard::Mode clipboardMode)
 {
-    QString clip = QApplication::clipboard()->text(clipboardMode);
+    QString clip = QGuiApplication::clipboard()->text(clipboardMode);
     if (!clip.isEmpty() || hasSelectedText()) {
         separate(); //make it a separate undo/redo command
         insert(clip);
@@ -1524,9 +1524,9 @@ void QWidgetLineControl::setBlinkingCursorEnabled(bool enable)
     m_blinkEnabled = enable;
 
     if (enable)
-        connect(qApp->styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetLineControl::updateCursorBlinking);
+        connect(QGuiApplication::styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetLineControl::updateCursorBlinking);
     else
-        disconnect(qApp->styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetLineControl::updateCursorBlinking);
+        disconnect(QGuiApplication::styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetLineControl::updateCursorBlinking);
 
     updateCursorBlinking();
 }
@@ -1680,7 +1680,7 @@ void QWidgetLineControl::processKeyEvent(QKeyEvent* event)
     if (event->key() == Qt::Key_Enter || event->key() == Qt::Key_Return) {
         if (hasAcceptableInput() || fixup()) {
 
-            QInputMethod *inputMethod = QApplication::inputMethod();
+            QInputMethod *inputMethod = QGuiApplication::inputMethod();
             inputMethod->commit();
             QWidget *lineEdit = qobject_cast<QWidget *>(parent());
             if (!(lineEdit && lineEdit->inputMethodHints() & Qt::ImhMultiLine))
diff --git a/src/widgets/widgets/qwidgettextcontrol.cpp b/src/widgets/widgets/qwidgettextcontrol.cpp
index af3b03cd9e..70e1c148a1 100644
--- a/src/widgets/widgets/qwidgettextcontrol.cpp
+++ b/src/widgets/widgets/qwidgettextcontrol.cpp
@@ -61,6 +61,9 @@
 #include "private/qtextdocument_p.h"
 #include "qtextlist.h"
 #include "private/qwidgettextcontrol_p.h"
+#if QT_CONFIG(style_stylesheet)
+#  include "private/qstylesheetstyle_p.h"
+#endif
 #if QT_CONFIG(graphicsview)
 #include "qgraphicssceneevent.h"
 #endif
@@ -94,7 +97,7 @@
 #include <qkeysequence.h>
 #define ACCEL_KEY(k) ((!QCoreApplication::testAttribute(Qt::AA_DontShowShortcutsInContextMenus) \
                        && QGuiApplication::styleHints()->showShortcutsInContextMenus()) \
-                      && !qApp->d_func()->shortcutMap.hasShortcutForKeySequence(k) ? \
+                      && !QGuiApplicationPrivate::instance()->shortcutMap.hasShortcutForKeySequence(k) ? \
                       QLatin1Char('\t') + QKeySequence(k).toString(QKeySequence::NativeText) : QString())
 
 #else
@@ -645,7 +648,7 @@ void QWidgetTextControlPrivate::_q_updateCurrentCharFormatAndSelection()
 #ifndef QT_NO_CLIPBOARD
 void QWidgetTextControlPrivate::setClipboardSelection()
 {
-    QClipboard *clipboard = QApplication::clipboard();
+    QClipboard *clipboard = QGuiApplication::clipboard();
     if (!cursor.hasSelection() || !clipboard->supportsSelection())
         return;
     Q_Q(QWidgetTextControl);
@@ -716,9 +719,9 @@ void QWidgetTextControlPrivate::setCursorVisible(bool visible)
     updateCursorBlinking();
 
     if (cursorVisible)
-        connect(qApp->styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetTextControlPrivate::updateCursorBlinking);
+        connect(QGuiApplication::styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetTextControlPrivate::updateCursorBlinking);
     else
-        disconnect(qApp->styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetTextControlPrivate::updateCursorBlinking);
+        disconnect(QGuiApplication::styleHints(), &QStyleHints::cursorFlashTimeChanged, this, &QWidgetTextControlPrivate::updateCursorBlinking);
 }
 
 void QWidgetTextControlPrivate::updateCursorBlinking()
@@ -956,12 +959,12 @@ void QWidgetTextControl::copy()
     if (!d->cursor.hasSelection())
         return;
     QMimeData *data = createMimeDataFromSelection();
-    QApplication::clipboard()->setMimeData(data);
+    QGuiApplication::clipboard()->setMimeData(data);
 }
 
 void QWidgetTextControl::paste(QClipboard::Mode mode)
 {
-    const QMimeData *md = QApplication::clipboard()->mimeData(mode);
+    const QMimeData *md = QGuiApplication::clipboard()->mimeData(mode);
     if (md)
         insertFromMimeData(md);
 }
@@ -1784,9 +1787,9 @@ void QWidgetTextControlPrivate::mouseReleaseEvent(QEvent *e, Qt::MouseButton but
         selectionChanged(true);
     } else if (button == Qt::MidButton
                && (interactionFlags & Qt::TextEditable)
-               && QApplication::clipboard()->supportsSelection()) {
+               && QGuiApplication::clipboard()->supportsSelection()) {
         setCursorPosition(pos);
-        const QMimeData *md = QApplication::clipboard()->mimeData(QClipboard::Selection);
+        const QMimeData *md = QGuiApplication::clipboard()->mimeData(QClipboard::Selection);
         if (md)
             q->insertFromMimeData(md);
 #endif
@@ -2479,7 +2482,7 @@ void QWidgetTextControl::setExtraSelections(const QList<QTextEdit::ExtraSelectio
     QHash<int, int> hash;
     for (int i = 0; i < d->extraSelections.count(); ++i) {
         const QAbstractTextDocumentLayout::Selection &esel = d->extraSelections.at(i);
-        hash.insertMulti(esel.cursor.anchor(), i);
+        hash.insert(esel.cursor.anchor(), i);
     }
 
     for (int i = 0; i < selections.count(); ++i) {
@@ -2595,7 +2598,7 @@ bool QWidgetTextControl::canPaste() const
 #ifndef QT_NO_CLIPBOARD
     Q_D(const QWidgetTextControl);
     if (d->interactionFlags & Qt::TextEditable) {
-        const QMimeData *md = QApplication::clipboard()->mimeData();
+        const QMimeData *md = QGuiApplication::clipboard()->mimeData();
         return md && canInsertFromMimeData(md);
     }
 #endif
@@ -3172,7 +3175,7 @@ QString QWidgetTextControl::toHtml() const
 }
 #endif
 
-#ifndef QT_NO_TEXTHTMLPARSER
+#if QT_CONFIG(textmarkdownwriter)
 QString QWidgetTextControl::toMarkdown(QTextDocument::MarkdownFeatures features) const
 {
     return document()->toMarkdown(features);
@@ -3256,6 +3259,15 @@ QAbstractTextDocumentLayout::PaintContext QWidgetTextControl::getPaintContext(QW
 
     ctx.selections = d->extraSelections;
     ctx.palette = d->palette;
+#if QT_CONFIG(style_stylesheet)
+    if (widget) {
+        if (auto cssStyle = qt_styleSheet(widget->style())) {
+            QStyleOption option;
+            option.initFrom(widget);
+            cssStyle->styleSheetPalette(widget, &option, &ctx.palette);
+        }
+    }
+#endif // style_stylesheet
     if (d->cursorOn && d->isEnabled) {
         if (d->hideCursor)
             ctx.cursorPosition = -1;
@@ -3319,7 +3331,7 @@ void QWidgetTextControlPrivate::_q_copyLink()
 #ifndef QT_NO_CLIPBOARD
     QMimeData *md = new QMimeData;
     md->setText(linkToCopy);
-    QApplication::clipboard()->setMimeData(md);
+    QGuiApplication::clipboard()->setMimeData(md);
 #endif
 }