Merge remote-tracking branch 'origin/5.14' into 5.15

Change-Id: Ifd83db69416230175ddc3161f640b612755018fc
2019-10-16 01:00:49 +02:00 · 2019-10-16 01:00:49 +02:00 · faab18c65a
commit faab18c65a
parent 06ca5c49e7 9cc040a806
87 changed files with 723 additions and 497 deletions
--- a/config.tests/arch/write_info.pri
+++ b/config.tests/arch/write_info.pri
@ -4,10 +4,7 @@ targetinfofile ~= s/pro$/target.txt/
 win32 {
    ext = .exe
 } else:wasm {
-    equals(WASM_OBJECT_FILES, 1): \
-        ext = .o
-    else: \
-        ext = .wasm
+    ext = .wasm
 }

 content = $${file_prefix}$${TARGET}$${ext}
--- a/examples/corelib/mimetypes/mimetypebrowser/main.cpp
+++ b/examples/corelib/mimetypes/mimetypebrowser/main.cpp
@ -51,7 +51,7 @@
 #include "mainwindow.h"

 #include <QApplication>
-#include <QDesktopWidget>
+#include <QScreen>

 #include <QCommandLineParser>
 #include <QCommandLineOption>
@ -68,7 +68,7 @@ int main(int argc, char *argv[])
    parser.process(app);

    MainWindow mainWindow;
-    const QRect availableGeometry = QApplication::desktop()->availableGeometry(&mainWindow);
+    const QRect availableGeometry = mainWindow.screen()->availableGeometry();
    mainWindow.resize(availableGeometry.width() / 3, availableGeometry.height() / 2);
    mainWindow.show();

--- a/examples/network/http/main.cpp
+++ b/examples/network/http/main.cpp
@ -49,8 +49,8 @@
 ****************************************************************************/

 #include <QApplication>
-#include <QDesktopWidget>
 #include <QDir>
+#include <QScreen>

 #include "httpwindow.h"

@ -59,7 +59,7 @@ int main(int argc, char *argv[])
    QApplication app(argc, argv);

    HttpWindow httpWin;
-    const QRect availableSize = QApplication::desktop()->availableGeometry(&httpWin);
+    const QRect availableSize = httpWin.screen()->availableGeometry();
    httpWin.resize(availableSize.width() / 5, availableSize.height() / 5);
    httpWin.move((availableSize.width() - httpWin.width()) / 2, (availableSize.height() - httpWin.height()) / 2);

--- a/examples/opengl/threadedqopenglwidget/main.cpp
+++ b/examples/opengl/threadedqopenglwidget/main.cpp
@ -50,7 +50,7 @@

 #include <QApplication>
 #include <QMainWindow>
-#include <QDesktopWidget>
+#include <QScreen>
 #include <QSurfaceFormat>
 #include <QOpenGLContext>
 #include <QCommandLineParser>
@ -90,7 +90,7 @@ int main( int argc, char ** argv )
    // The rendering for the four QOpenGLWidgets happens on four separate threads.

    GLWidget topLevelGlWidget;
-    QPoint pos = QApplication::desktop()->availableGeometry(&topLevelGlWidget).topLeft() + QPoint(200, 200);
+    QPoint pos = topLevelGlWidget.screen()->availableGeometry().topLeft() + QPoint(200, 200);
    topLevelGlWidget.setWindowTitle(QStringLiteral("Threaded QOpenGLWidget example top level"));
    topLevelGlWidget.resize(200, 200);
    topLevelGlWidget.move(pos);
--- a/examples/widgets/desktop/screenshot/main.cpp
+++ b/examples/widgets/desktop/screenshot/main.cpp
@ -49,7 +49,7 @@
 ****************************************************************************/

 #include <QApplication>
-#include <QDesktopWidget>
+#include <QScreen>

 #include "screenshot.h"

@ -58,7 +58,8 @@ int main(int argc, char *argv[])
    QApplication app(argc, argv);

    Screenshot screenshot;
-    screenshot.move(QApplication::desktop()->availableGeometry(&screenshot).topLeft() + QPoint(20, 20));
+    screenshot.move(screenshot.screen()->availableGeometry().topLeft() + QPoint(20, 20));
    screenshot.show();
+
    return app.exec();
 }
--- a/examples/widgets/desktop/screenshot/screenshot.cpp
+++ b/examples/widgets/desktop/screenshot/screenshot.cpp
@ -59,7 +59,7 @@ Screenshot::Screenshot()
    screenshotLabel->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
    screenshotLabel->setAlignment(Qt::AlignCenter);

-    const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
+    const QRect screenGeometry = screen()->geometry();
    screenshotLabel->setMinimumSize(screenGeometry.width() / 8, screenGeometry.height() / 8);

    QVBoxLayout *mainLayout = new QVBoxLayout(this);
--- a/examples/widgets/dialogs/standarddialogs/main.cpp
+++ b/examples/widgets/dialogs/standarddialogs/main.cpp
@ -49,8 +49,8 @@
 ****************************************************************************/

 #include <QApplication>
+#include <QScreen>
 #include <QStyleHints>
-#include <QDesktopWidget>
 #include <QTranslator>
 #include <QLocale>
 #include <QLibraryInfo>
@ -73,7 +73,7 @@ int main(int argc, char *argv[])

    Dialog dialog;
    if (!QGuiApplication::styleHints()->showIsFullScreen() && !QGuiApplication::styleHints()->showIsMaximized()) {
-        const QRect availableGeometry = QApplication::desktop()->availableGeometry(&dialog);
+        const QRect availableGeometry = dialog.screen()->availableGeometry();
        dialog.resize(availableGeometry.width() / 3, availableGeometry.height() * 2 / 3);
        dialog.move((availableGeometry.width() - dialog.width()) / 2,
                    (availableGeometry.height() - dialog.height()) / 2);
--- a/examples/widgets/itemviews/dirview/main.cpp
+++ b/examples/widgets/itemviews/dirview/main.cpp
@ -49,9 +49,9 @@
 ****************************************************************************/

 #include <QApplication>
-#include <QDesktopWidget>
 #include <QFileSystemModel>
 #include <QFileIconProvider>
+#include <QScreen>
 #include <QTreeView>
 #include <QCommandLineParser>
 #include <QCommandLineOption>
@ -92,7 +92,7 @@ int main(int argc, char *argv[])
    tree.setAnimated(false);
    tree.setIndentation(20);
    tree.setSortingEnabled(true);
-    const QSize availableSize = QApplication::desktop()->availableGeometry(&tree).size();
+    const QSize availableSize = tree.screen()->availableGeometry().size();
    tree.resize(availableSize / 2);
    tree.setColumnWidth(0, tree.width() / 3);

--- a/examples/widgets/mainwindows/application/mainwindow.cpp
+++ b/examples/widgets/mainwindows/application/mainwindow.cpp
@ -281,7 +281,7 @@ void MainWindow::readSettings()
    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
    const QByteArray geometry = settings.value("geometry", QByteArray()).toByteArray();
    if (geometry.isEmpty()) {
-        const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+        const QRect availableGeometry = screen()->availableGeometry();
        resize(availableGeometry.width() / 3, availableGeometry.height() / 2);
        move((availableGeometry.width() - width()) / 2,
             (availableGeometry.height() - height()) / 2);
--- a/examples/widgets/mainwindows/mdi/mainwindow.cpp
+++ b/examples/widgets/mainwindows/mdi/mainwindow.cpp
@ -464,7 +464,7 @@ void MainWindow::readSettings()
    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
    const QByteArray geometry = settings.value("geometry", QByteArray()).toByteArray();
    if (geometry.isEmpty()) {
-        const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+        const QRect availableGeometry = screen()->availableGeometry();
        resize(availableGeometry.width() / 3, availableGeometry.height() / 2);
        move((availableGeometry.width() - width()) / 2,
             (availableGeometry.height() - height()) / 2);
--- a/examples/widgets/mainwindows/sdi/mainwindow.cpp
+++ b/examples/widgets/mainwindows/sdi/mainwindow.cpp
@ -167,7 +167,7 @@ void MainWindow::tile(const QMainWindow *previous)
    if (!topFrameWidth)
        topFrameWidth = 40;
    const QPoint pos = previous->pos() + 2 * QPoint(topFrameWidth, topFrameWidth);
-    if (QApplication::desktop()->availableGeometry(this).contains(rect().bottomRight() + pos))
+    if (screen()->availableGeometry().contains(rect().bottomRight() + pos))
        move(pos);
 }

@ -290,7 +290,7 @@ void MainWindow::readSettings()
    QSettings settings(QCoreApplication::organizationName(), QCoreApplication::applicationName());
    const QByteArray geometry = settings.value("geometry", QByteArray()).toByteArray();
    if (geometry.isEmpty()) {
-        const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+        const QRect availableGeometry = screen()->availableGeometry();
        resize(availableGeometry.width() / 3, availableGeometry.height() / 2);
        move((availableGeometry.width() - width()) / 2,
             (availableGeometry.height() - height()) / 2);
--- a/examples/widgets/richtext/textedit/main.cpp
+++ b/examples/widgets/richtext/textedit/main.cpp
@ -51,9 +51,9 @@
 #include "textedit.h"

 #include <QApplication>
-#include <QDesktopWidget>
 #include <QCommandLineParser>
 #include <QCommandLineOption>
+#include <QScreen>

 int main(int argc, char *argv[])
 {
@ -72,7 +72,7 @@ int main(int argc, char *argv[])

    TextEdit mw;

-    const QRect availableGeometry = QApplication::desktop()->availableGeometry(&mw);
+    const QRect availableGeometry = mw.screen()->availableGeometry();
    mw.resize(availableGeometry.width() / 2, (availableGeometry.height() * 2) / 3);
    mw.move((availableGeometry.width() - mw.width()) / 2,
            (availableGeometry.height() - mw.height()) / 2);
--- a/examples/widgets/tools/codecs/mainwindow.cpp
+++ b/examples/widgets/tools/codecs/mainwindow.cpp
@ -54,12 +54,12 @@

 #include <QAction>
 #include <QApplication>
-#include <QDesktopWidget>
 #include <QFileDialog>
 #include <QMenuBar>
 #include <QMessageBox>
 #include <QPlainTextEdit>
 #include <QRegularExpression>
+#include <QScreen>
 #include <QTextCodec>
 #include <QTextStream>

@ -78,7 +78,7 @@ MainWindow::MainWindow()

    setWindowTitle(tr("Codecs"));

-    const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
+    const QRect screenGeometry = screen()->geometry();
    resize(screenGeometry.width() / 2, screenGeometry.height() * 2 / 3);
 }

@ -216,7 +216,7 @@ void MainWindow::encodingDialog()
 {
    if (!m_encodingDialog) {
        m_encodingDialog = new EncodingDialog(this);
-        const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
+        const QRect screenGeometry = screen()->geometry();
        m_encodingDialog->setMinimumWidth(screenGeometry.width() / 4);
    }
    m_encodingDialog->show();
--- a/examples/widgets/tools/codecs/previewform.cpp
+++ b/examples/widgets/tools/codecs/previewform.cpp
@ -52,12 +52,12 @@

 #include <QApplication>
 #include <QComboBox>
-#include <QDesktopWidget>
 #include <QDialogButtonBox>
 #include <QGridLayout>
 #include <QLabel>
 #include <QPlainTextEdit>
 #include <QPushButton>
+#include <QScreen>
 #include <QTextCodec>
 #include <QTextStream>

@ -183,7 +183,7 @@ PreviewForm::PreviewForm(QWidget *parent)
    mainLayout->addWidget(statusLabel, 2, 0, 1, 2);
    mainLayout->addWidget(buttonBox, 3, 0, 1, 2);

-    const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
+    const QRect screenGeometry = screen()->geometry();
    resize(screenGeometry.width() * 2 / 5, screenGeometry.height() / 2);
 }

--- a/examples/widgets/tools/settingseditor/mainwindow.cpp
+++ b/examples/widgets/tools/settingseditor/mainwindow.cpp
@ -54,12 +54,12 @@

 #include <QAction>
 #include <QApplication>
-#include <QDesktopWidget>
 #include <QFileDialog>
 #include <QInputDialog>
 #include <QLineEdit>
 #include <QMenuBar>
 #include <QMessageBox>
+#include <QScreen>
 #include <QStandardPaths>
 #include <QStatusBar>

@ -74,7 +74,7 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
    fallbacksAct->setChecked(true);

    setWindowTitle(QCoreApplication::applicationName());
-    const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+    const QRect availableGeometry = screen()->availableGeometry();
    adjustSize();
    move((availableGeometry.width() - width()) / 2, (availableGeometry.height() - height()) / 2);
 }
--- a/examples/widgets/tools/settingseditor/settingstree.cpp
+++ b/examples/widgets/tools/settingseditor/settingstree.cpp
@ -52,8 +52,8 @@
 #include "variantdelegate.h"

 #include <QApplication>
-#include <QDesktopWidget>
 #include <QHeaderView>
+#include <QScreen>
 #include <QSettings>

 SettingsTree::SettingsTree(QWidget *parent)
@ -93,7 +93,7 @@ void SettingsTree::setSettingsObject(const SettingsPtr &newSettings)

 QSize SettingsTree::sizeHint() const
 {
-    const QRect availableGeometry = QApplication::desktop()->availableGeometry(this);
+    const QRect availableGeometry = screen()->availableGeometry();
    return QSize(availableGeometry.width() * 2 / 3, availableGeometry.height() * 2 / 3);
 }

--- a/examples/widgets/widgets/charactermap/mainwindow.cpp
+++ b/examples/widgets/widgets/charactermap/mainwindow.cpp
@ -64,6 +64,7 @@
 #include <QMenuBar>
 #include <QPlainTextEdit>
 #include <QPushButton>
+#include <QScreen>
 #include <QScrollArea>
 #include <QStatusBar>
 #include <QTextStream>
@ -302,7 +303,7 @@ QString FontInfoDialog::text() const

 void MainWindow::showInfo()
 {
-    const QRect screenGeometry = QApplication::desktop()->screenGeometry(this);
+    const QRect screenGeometry = screen()->geometry();
    FontInfoDialog *dialog = new FontInfoDialog(this);
    dialog->setWindowTitle(tr("Fonts"));
    dialog->setAttribute(Qt::WA_DeleteOnClose);
--- a/examples/widgets/widgets/icons/main.cpp
+++ b/examples/widgets/widgets/icons/main.cpp
@ -50,7 +50,7 @@

 #include <QApplication>
 #include <QCommandLineParser>
-#include <QDesktopWidget>
+#include <QScreen>

 #include "mainwindow.h"

@ -77,7 +77,7 @@ int main(int argc, char *argv[])
    if (!commandLineParser.positionalArguments().isEmpty())
        mainWin.loadImages(commandLineParser.positionalArguments());

-    const QRect availableGeometry = QApplication::desktop()->availableGeometry(&mainWin);
+    const QRect availableGeometry = mainWin.screen()->availableGeometry();
    mainWin.resize(availableGeometry.width() / 2, availableGeometry.height() * 2 / 3);
    mainWin.move((availableGeometry.width() - mainWin.width()) / 2, (availableGeometry.height() - mainWin.height()) / 2);

--- a/examples/xml/dombookmarks/mainwindow.cpp
+++ b/examples/xml/dombookmarks/mainwindow.cpp
@ -63,7 +63,7 @@ MainWindow::MainWindow()
    statusBar()->showMessage(tr("Ready"));

    setWindowTitle(tr("DOM Bookmarks"));
-    const QSize availableSize = QApplication::desktop()->availableGeometry(this).size();
+    const QSize availableSize = screen()->availableGeometry().size();
    resize(availableSize.width() / 2, availableSize.height() / 3);
 }

--- a/examples/xml/saxbookmarks/mainwindow.cpp
+++ b/examples/xml/saxbookmarks/mainwindow.cpp
@ -74,7 +74,7 @@ MainWindow::MainWindow()
    statusBar()->showMessage(tr("Ready"));

    setWindowTitle(tr("SAX Bookmarks"));
-    const QSize availableSize = QApplication::desktop()->availableGeometry(this).size();
+    const QSize availableSize = screen()->availableGeometry().size();
    resize(availableSize.width() / 2, availableSize.height() / 3);
 }

--- a/examples/xml/streambookmarks/mainwindow.cpp
+++ b/examples/xml/streambookmarks/mainwindow.cpp
@ -75,7 +75,7 @@ MainWindow::MainWindow()
    statusBar()->showMessage(tr("Ready"));

    setWindowTitle(tr("QXmlStream Bookmarks"));
-    const QSize availableSize = QApplication::desktop()->availableGeometry(this).size();
+    const QSize availableSize = screen()->availableGeometry().size();
    resize(availableSize.width() / 2, availableSize.height() / 3);
 }
 //! [0]
--- a/src/corelib/global/qglobal.cpp
+++ b/src/corelib/global/qglobal.cpp
@ -47,12 +47,11 @@
 #include "qoperatingsystemversion.h"
 #include "qoperatingsystemversion_p.h"
 #if defined(Q_OS_WIN) || defined(Q_OS_CYGWIN) || defined(Q_OS_WINRT)
-#include "qoperatingsystemversion_win_p.h"
-#  if QT_CONFIG(settings)
-#    include "qsettings.h"
-#    include "qvariant.h"
+#  include "qoperatingsystemversion_win_p.h"
+#  ifndef Q_OS_WINRT
+#    include "private/qwinregistry_p.h"
 #  endif
-#endif
+#endif // Q_OS_WIN || Q_OS_CYGWIN
 #include <private/qlocale_tools_p.h>

 #include <qmutex.h>
@ -2190,28 +2189,25 @@ const QSysInfo::WinVersion QSysInfo::WindowsVersion = QSysInfo::windowsVersion()
 QT_WARNING_POP
 #endif

-static QString readRegistryString(const QString &key, const QString &subKey)
+static QString readVersionRegistryString(const wchar_t *subKey)
 {
-#if QT_CONFIG(settings)
-    QSettings settings(key, QSettings::NativeFormat);
-    return settings.value(subKey).toString();
+#if !defined(QT_BUILD_QMAKE) && !defined(Q_OS_WINRT)
+     return QWinRegistryKey(HKEY_LOCAL_MACHINE, LR"(SOFTWARE\Microsoft\Windows NT\CurrentVersion)")
+            .stringValue(subKey);
 #else
-    Q_UNUSED(key);
-    Q_UNUSED(subKey);
-    return QString();
+     Q_UNUSED(subKey);
+     return QString();
 #endif
 }

-static inline QString windowsVersionKey() { return QStringLiteral(R"(HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion)"); }
-
 static inline QString windows10ReleaseId()
 {
-    return readRegistryString(windowsVersionKey(), QStringLiteral("ReleaseId"));
+    return readVersionRegistryString(L"ReleaseId");
 }

 static inline QString windows7Build()
 {
-    return readRegistryString(windowsVersionKey(), QStringLiteral("CurrentBuild"));
+    return readVersionRegistryString(L"CurrentBuild");
 }

 static QString winSp_helper()
@ -3078,6 +3074,7 @@ QByteArray QSysInfo::machineUniqueId()
    }
 #elif defined(Q_OS_WIN) && !defined(Q_OS_WINRT)
    // Let's poke at the registry
+    // ### Qt 6: Use new helpers from qwinregistry.cpp (once bootstrap builds are obsolete)
    HKEY key = NULL;
    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Microsoft\\Cryptography", 0, KEY_READ | KEY_WOW64_64KEY, &key)
            == ERROR_SUCCESS) {
--- a/src/corelib/io/qsettings_win.cpp
+++ b/src/corelib/io/qsettings_win.cpp
@ -136,6 +136,8 @@ static void mergeKeySets(NameSet *dest, const QStringList &src)
 ** Wrappers for the insane windows registry API
 */

+// ### Qt 6: Use new helpers from qwinregistry.cpp (once bootstrap builds are obsolete)
+
 // Open a key with the specified "perms".
 // "access" is to explicitly use the 32- or 64-bit branch.
 static HKEY openKey(HKEY parentHandle, REGSAM perms, const QString &rSubKey, REGSAM access = 0)
--- a/src/corelib/kernel/kernel.pri
+++ b/src/corelib/kernel/kernel.pri
@ -88,8 +88,10 @@ win32 {
            SOURCES += kernel/qeventdispatcher_winrt.cpp
            HEADERS += kernel/qeventdispatcher_winrt_p.h
        } else {
-            SOURCES += kernel/qeventdispatcher_win.cpp
-            HEADERS += kernel/qeventdispatcher_win_p.h
+            SOURCES += kernel/qeventdispatcher_win.cpp \
+                       kernel/qwinregistry.cpp
+            HEADERS += kernel/qeventdispatcher_win_p.h \
+                       kernel/qwinregistry_p.h
        }

        !winrt: LIBS_PRIVATE += -lversion
--- a/src/corelib/kernel/qwinregistry.cpp
+++ b/src/corelib/kernel/qwinregistry.cpp
@ -0,0 +1,120 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore 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 "qwinregistry_p.h"
+
+#include <QtCore/qvarlengtharray.h>
+
+#include <algorithm>
+
+QT_BEGIN_NAMESPACE
+
+QWinRegistryKey::QWinRegistryKey() :
+    m_key(nullptr)
+{
+}
+
+// Open a key with the specified permissions (KEY_READ/KEY_WRITE).
+// "access" is to explicitly use the 32- or 64-bit branch.
+QWinRegistryKey::QWinRegistryKey(HKEY parentHandle, QStringView subKey,
+                                 REGSAM permissions, REGSAM access)
+{
+    if (RegOpenKeyEx(parentHandle, reinterpret_cast<const wchar_t *>(subKey.utf16()),
+                     0, permissions | access, &m_key) != ERROR_SUCCESS) {
+        m_key = nullptr;
+    }
+}
+
+QWinRegistryKey::~QWinRegistryKey()
+{
+    close();
+}
+
+void QWinRegistryKey::close()
+{
+    if (isValid()) {
+        RegCloseKey(m_key);
+        m_key = nullptr;
+    }
+}
+
+QString QWinRegistryKey::stringValue(QStringView subKey) const
+{
+    QString result;
+    if (!isValid())
+        return result;
+    DWORD type;
+    DWORD size;
+    auto subKeyC = reinterpret_cast<const wchar_t *>(subKey.utf16());
+    if (RegQueryValueEx(m_key, subKeyC, nullptr, &type, nullptr, &size) != ERROR_SUCCESS
+        || (type != REG_SZ && type != REG_EXPAND_SZ) || size <= 2) {
+        return result;
+    }
+    // Reserve more for rare cases where trailing '\0' are missing in registry,
+    // otherwise chop off the '\0' received.
+    QString buffer(int(size / sizeof(wchar_t)), Qt::Uninitialized);
+    if (RegQueryValueEx(m_key, subKeyC, nullptr, &type,
+                        reinterpret_cast<LPBYTE>(buffer.data()), &size) == ERROR_SUCCESS) {
+        if (buffer.endsWith(QChar::Null))
+            buffer.chop(1);
+    } else {
+        buffer.clear();
+    }
+    return buffer;
+}
+
+QPair<DWORD, bool> QWinRegistryKey::dwordValue(QStringView subKey) const
+{
+    if (!isValid())
+        return qMakePair(0, false);
+    DWORD type;
+    auto subKeyC = reinterpret_cast<const wchar_t *>(subKey.utf16());
+    if (RegQueryValueEx(m_key, subKeyC, nullptr, &type, nullptr, nullptr) != ERROR_SUCCESS
+        || type != REG_DWORD) {
+        return qMakePair(0, false);
+    }
+    DWORD value = 0;
+    DWORD size = sizeof(value);
+    const bool ok =
+        RegQueryValueEx(m_key, subKeyC, nullptr, nullptr,
+                        reinterpret_cast<unsigned char *>(&value), &size) == ERROR_SUCCESS;
+    return qMakePair(value, ok);
+}
+
+QT_END_NAMESPACE
--- a/src/corelib/kernel/qwinregistry_p.h
+++ b/src/corelib/kernel/qwinregistry_p.h
@ -0,0 +1,89 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore 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 QWINREGISTRY_H
+#define QWINREGISTRY_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API. It exists purely as an
+// implementation detail. This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtCore/qpair.h>
+#include <QtCore/qstring.h>
+#include <QtCore/qstringview.h>
+#include <QtCore/qt_windows.h>
+
+QT_BEGIN_NAMESPACE
+
+class Q_CORE_EXPORT QWinRegistryKey
+{
+public:
+    Q_DISABLE_COPY(QWinRegistryKey)
+
+    QWinRegistryKey();
+    explicit QWinRegistryKey(HKEY parentHandle, QStringView subKey,
+                             REGSAM permissions = KEY_READ, REGSAM access = 0);
+    ~QWinRegistryKey();
+
+    QWinRegistryKey(QWinRegistryKey &&other) noexcept { swap(other); }
+    QWinRegistryKey &operator=(QWinRegistryKey &&other) noexcept { swap(other); return *this; }
+
+    void swap(QWinRegistryKey &other) noexcept { qSwap(m_key, other.m_key); }
+
+    bool isValid() const { return m_key != nullptr; }
+    operator HKEY() const { return m_key; }
+    void close();
+
+    QString stringValue(QStringView subKey) const;
+    QPair<DWORD, bool> dwordValue(QStringView subKey) const;
+
+private:
+    HKEY m_key;
+};
+
+QT_END_NAMESPACE
+
+#endif // QWINREGISTRY_H
--- a/src/corelib/time/qtimezoneprivate_win.cpp
+++ b/src/corelib/time/qtimezoneprivate_win.cpp
@ -46,13 +46,14 @@

 #include <algorithm>

-QT_BEGIN_NAMESPACE
-
 #ifndef Q_OS_WINRT
+#include <private/qwinregistry_p.h>
 // The registry-based timezone backend is not available on WinRT, which falls back to equivalent APIs.
 #define QT_USE_REGISTRY_TIMEZONE 1
 #endif

+QT_BEGIN_NAMESPACE
+
 /*
    Private

@ -71,8 +72,8 @@ QT_BEGIN_NAMESPACE
 // Vista introduced support for historic data, see MSDN docs on DYNAMIC_TIME_ZONE_INFORMATION
 // http://msdn.microsoft.com/en-gb/library/windows/desktop/ms724253%28v=vs.85%29.aspx
 #ifdef QT_USE_REGISTRY_TIMEZONE
-static const char tzRegPath[] = "SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\Time Zones";
-static const char currTzRegPath[] = "SYSTEM\\CurrentControlSet\\Control\\TimeZoneInformation";
+static const wchar_t tzRegPath[] = LR"(SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones)";
+static const wchar_t currTzRegPath[] = LR"(SYSTEM\CurrentControlSet\Control\TimeZoneInformation)";
 #endif

 enum {
@ -138,27 +139,6 @@ bool equalTzi(const TIME_ZONE_INFORMATION &tzi1, const TIME_ZONE_INFORMATION &tz
 }

 #ifdef QT_USE_REGISTRY_TIMEZONE
-bool openRegistryKey(const QString &keyPath, HKEY *key)
-{
-    return RegOpenKeyEx(HKEY_LOCAL_MACHINE, reinterpret_cast<const wchar_t*>(keyPath.utf16()),
-                        0, KEY_READ, key) == ERROR_SUCCESS;
-}
-
-QString readRegistryString(const HKEY &key, const wchar_t *value)
-{
-    wchar_t buffer[MAX_PATH] = {0};
-    DWORD size = sizeof(wchar_t) * MAX_PATH;
-    RegQueryValueEx(key, value, nullptr, nullptr, reinterpret_cast<LPBYTE>(buffer), &size);
-    return QString::fromWCharArray(buffer);
-}
-
-int readRegistryValue(const HKEY &key, const wchar_t *value)
-{
-    DWORD buffer;
-    DWORD size = sizeof(buffer);
-    RegQueryValueEx(key, value, nullptr, nullptr, reinterpret_cast<LPBYTE>(&buffer), &size);
-    return buffer;
-}

 QWinTimeZonePrivate::QWinTransitionRule readRegistryRule(const HKEY &key,
                                                         const wchar_t *value, bool *ok)
@ -185,12 +165,11 @@ TIME_ZONE_INFORMATION getRegistryTzi(const QByteArray &windowsId, bool *ok)
    TIME_ZONE_INFORMATION tzi;
    REG_TZI_FORMAT regTzi;
    DWORD regTziSize = sizeof(regTzi);
-    HKEY key = NULL;
-    const QString tziKeyPath = QString::fromUtf8(tzRegPath) + QLatin1Char('\\')
+    const QString tziKeyPath = QString::fromWCharArray(tzRegPath) + QLatin1Char('\\')
                               + QString::fromUtf8(windowsId);

-    if (openRegistryKey(tziKeyPath, &key)) {
-
+    QWinRegistryKey key(HKEY_LOCAL_MACHINE, tziKeyPath);
+    if (key.isValid()) {
        DWORD size = sizeof(tzi.DaylightName);
        RegQueryValueEx(key, L"Dlt", nullptr, nullptr, reinterpret_cast<LPBYTE>(tzi.DaylightName), &size);

@ -206,8 +185,6 @@ TIME_ZONE_INFORMATION getRegistryTzi(const QByteArray &windowsId, bool *ok)
            tzi.DaylightDate = regTzi.DaylightDate;
            *ok = true;
        }
-
-        RegCloseKey(key);
    }

    return tzi;
@ -299,8 +276,8 @@ QList<QByteArray> availableWindowsIds()
 #ifdef QT_USE_REGISTRY_TIMEZONE
    // TODO Consider caching results in a global static, very unlikely to change.
    QList<QByteArray> list;
-    HKEY key = NULL;
-    if (openRegistryKey(QString::fromUtf8(tzRegPath), &key)) {
+    QWinRegistryKey key(HKEY_LOCAL_MACHINE, tzRegPath);
+    if (key.isValid()) {
        DWORD idCount = 0;
        if (RegQueryInfoKey(key, 0, 0, 0, &idCount, 0, 0, 0, 0, 0, 0, 0) == ERROR_SUCCESS
            && idCount > 0) {
@ -311,7 +288,6 @@ QList<QByteArray> availableWindowsIds()
                    list.append(QString::fromWCharArray(buffer).toUtf8());
            }
        }
-        RegCloseKey(key);
    }
    return list;
 #else // QT_USE_REGISTRY_TIMEZONE
@ -325,15 +301,10 @@ QByteArray windowsSystemZoneId()
 {
 #ifdef QT_USE_REGISTRY_TIMEZONE
    // On Vista and later is held in the value TimeZoneKeyName in key currTzRegPath
-    QString id;
-    HKEY key = NULL;
-    QString tziKeyPath = QString::fromUtf8(currTzRegPath);
-    if (openRegistryKey(tziKeyPath, &key)) {
-        id = readRegistryString(key, L"TimeZoneKeyName");
-        RegCloseKey(key);
-        if (!id.isEmpty())
-            return std::move(id).toUtf8();
-    }
+    const QString id = QWinRegistryKey(HKEY_LOCAL_MACHINE, currTzRegPath)
+                       .stringValue(L"TimeZoneKeyName");
+    if (!id.isEmpty())
+        return id.toUtf8();

    // On XP we have to iterate over the zones until we find a match on
    // names/offsets with the current data
@ -575,22 +546,22 @@ void QWinTimeZonePrivate::init(const QByteArray &ianaId)
    if (!m_windowsId.isEmpty()) {
 #ifdef QT_USE_REGISTRY_TIMEZONE
        // Open the base TZI for the time zone
-        HKEY baseKey = NULL;
-        const QString baseKeyPath = QString::fromUtf8(tzRegPath) + QLatin1Char('\\')
+        const QString baseKeyPath = QString::fromWCharArray(tzRegPath) + QLatin1Char('\\')
                                   + QString::fromUtf8(m_windowsId);
-        if (openRegistryKey(baseKeyPath, &baseKey)) {
+        QWinRegistryKey baseKey(HKEY_LOCAL_MACHINE, baseKeyPath);
+        if (baseKey.isValid()) {
            //  Load the localized names
-            m_displayName = readRegistryString(baseKey, L"Display");
-            m_standardName = readRegistryString(baseKey, L"Std");
-            m_daylightName = readRegistryString(baseKey, L"Dlt");
+            m_displayName = baseKey.stringValue(L"Display");
+            m_standardName = baseKey.stringValue(L"Std");
+            m_daylightName = baseKey.stringValue(L"Dlt");
            // On Vista and later the optional dynamic key holds historic data
            const QString dynamicKeyPath = baseKeyPath + QLatin1String("\\Dynamic DST");
-            HKEY dynamicKey = NULL;
-            if (openRegistryKey(dynamicKeyPath, &dynamicKey)) {
+            QWinRegistryKey dynamicKey(HKEY_LOCAL_MACHINE, dynamicKeyPath);
+            if (dynamicKey.isValid()) {
                // Find out the start and end years stored, then iterate over them
-                int startYear = readRegistryValue(dynamicKey, L"FirstEntry");
-                int endYear = readRegistryValue(dynamicKey, L"LastEntry");
-                for (int year = startYear; year <= endYear; ++year) {
+                const auto startYear = dynamicKey.dwordValue(L"FirstEntry");
+                const auto endYear = dynamicKey.dwordValue(L"LastEntry");
+                for (int year = int(startYear.first); year <= int(endYear.first); ++year) {
                    bool ruleOk;
                    QWinTransitionRule rule = readRegistryRule(dynamicKey,
                                                               reinterpret_cast<LPCWSTR>(QString::number(year).utf16()),
@ -611,7 +582,6 @@ void QWinTimeZonePrivate::init(const QByteArray &ianaId)
                        m_tranRules.append(rule);
                    }
                }
-                RegCloseKey(dynamicKey);
            } else {
                // No dynamic data so use the base data
                bool ruleOk;
@ -620,7 +590,6 @@ void QWinTimeZonePrivate::init(const QByteArray &ianaId)
                if (ruleOk)
                    m_tranRules.append(rule);
            }
-            RegCloseKey(baseKey);
        }
 #else // QT_USE_REGISTRY_TIMEZONE
        if (gTimeZones->isEmpty())
--- a/src/gui/rhi/qrhigles2.cpp
+++ b/src/gui/rhi/qrhigles2.cpp
@ -525,6 +525,11 @@ void QRhiGles2::destroy()
    ensureContext();
    executeDeferredReleases();

+    if (vao) {
+        f->glDeleteVertexArrays(1, &vao);
+        vao = 0;
+    }
+
    for (uint shader : m_shaderCache)
        f->glDeleteShader(shader);
    m_shaderCache.clear();
@ -1151,6 +1156,13 @@ const QRhiNativeHandles *QRhiGles2::nativeHandles(QRhiCommandBuffer *cb)
    return nullptr;
 }

+static void addBoundaryCommand(QGles2CommandBuffer *cbD, QGles2CommandBuffer::Command::Cmd type)
+{
+    QGles2CommandBuffer::Command cmd;
+    cmd.cmd = type;
+    cbD->commands.append(cmd);
+}
+
 void QRhiGles2::beginExternal(QRhiCommandBuffer *cb)
 {
    if (ofr.active) {
@ -1166,6 +1178,9 @@ void QRhiGles2::beginExternal(QRhiCommandBuffer *cb)
    QGles2CommandBuffer *cbD = QRHI_RES(QGles2CommandBuffer, cb);
    executeCommandBuffer(cbD);
    cbD->resetCommands();
+
+    if (vao)
+        f->glBindVertexArray(0);
 }

 void QRhiGles2::endExternal(QRhiCommandBuffer *cb)
@ -1183,17 +1198,12 @@ void QRhiGles2::endExternal(QRhiCommandBuffer *cb)
        enqueueBarriersForPass(cbD);
    }

+    addBoundaryCommand(cbD, QGles2CommandBuffer::Command::ResetFrame);
+
    if (cbD->currentTarget)
        enqueueBindFramebuffer(cbD->currentTarget, cbD);
 }

-static void addBoundaryCommand(QGles2CommandBuffer *cb, QGles2CommandBuffer::Command::Cmd type)
-{
-    QGles2CommandBuffer::Command cmd;
-    cmd.cmd = type;
-    cb->commands.append(cmd);
-}
-
 QRhi::FrameOpResult QRhiGles2::beginFrame(QRhiSwapChain *swapChain, QRhi::BeginFrameFlags flags)
 {
    Q_UNUSED(flags);
@ -1913,6 +1923,10 @@ void QRhiGles2::executeCommandBuffer(QRhiCommandBuffer *cb)
            if (vao)
                f->glBindVertexArray(0);
            break;
+        case QGles2CommandBuffer::Command::ResetFrame:
+            if (vao)
+                f->glBindVertexArray(vao);
+            break;
        case QGles2CommandBuffer::Command::Viewport:
            f->glViewport(GLint(cmd.args.viewport.x), GLint(cmd.args.viewport.y), GLsizei(cmd.args.viewport.w), GLsizei(cmd.args.viewport.h));
            f->glDepthRangef(cmd.args.viewport.d0, cmd.args.viewport.d1);
--- a/src/gui/rhi/qrhigles2_p_p.h
+++ b/src/gui/rhi/qrhigles2_p_p.h
@ -300,6 +300,7 @@ struct QGles2CommandBuffer : public QRhiCommandBuffer
        enum Cmd {
            BeginFrame,
            EndFrame,
+            ResetFrame,
            Viewport,
            Scissor,
            BlendConstants,
--- a/src/platformsupport/fontdatabases/mac/qcoretextfontdatabase.mm
+++ b/src/platformsupport/fontdatabases/mac/qcoretextfontdatabase.mm
@ -432,88 +432,142 @@ template class QCoreTextFontDatabaseEngineFactory<QCoreTextFontEngine>;
 template class QCoreTextFontDatabaseEngineFactory<QFontEngineFT>;
 #endif

-QStringList QCoreTextFontDatabase::fallbacksForFamily(const QString &family)
+CTFontDescriptorRef descriptorForFamily(const QString &familyName)
+{
+    return CTFontDescriptorCreateWithAttributes(CFDictionaryRef(@{
+        (id)kCTFontFamilyNameAttribute: familyName.toNSString()
+    }));
+}
+
+CTFontDescriptorRef descriptorForFamily(const char *familyName)
+{
+    return descriptorForFamily(QString::fromLatin1(familyName));
+}
+
+CFArrayRef fallbacksForDescriptor(CTFontDescriptorRef descriptor)
+{
+    QCFType<CTFontRef> font = CTFontCreateWithFontDescriptor(descriptor, 0.0, nullptr);
+    if (!font) {
+        qCWarning(lcQpaFonts) << "Failed to create fallback font for" << descriptor;
+        return nullptr;
+    }
+
+    CFArrayRef cascadeList = CFArrayRef(CTFontCopyDefaultCascadeListForLanguages(font,
+        (CFArrayRef)[NSUserDefaults.standardUserDefaults stringArrayForKey:@"AppleLanguages"]));
+
+    if (!cascadeList) {
+        qCWarning(lcQpaFonts) << "Failed to create fallback cascade list for" << descriptor;
+        return nullptr;
+    }
+
+    return cascadeList;
+}
+
+CFArrayRef QCoreTextFontDatabase::fallbacksForFamily(const QString &family)
 {
    if (family.isEmpty())
-        return QStringList();
+        return nullptr;

-    auto attributes = @{ id(kCTFontFamilyNameAttribute): family.toNSString() };
-    QCFType<CTFontDescriptorRef> fontDescriptor = CTFontDescriptorCreateWithAttributes(CFDictionaryRef(attributes));
+    QCFType<CTFontDescriptorRef> fontDescriptor = descriptorForFamily(family);
    if (!fontDescriptor) {
        qCWarning(lcQpaFonts) << "Failed to create fallback font descriptor for" << family;
-        return QStringList();
+        return nullptr;
    }

-    QCFType<CTFontRef> font = CTFontCreateWithFontDescriptor(fontDescriptor, 12.0, 0);
-    if (!font) {
-        qCWarning(lcQpaFonts) << "Failed to create fallback font for" << family;
-        return QStringList();
-    }
+    // If the font is not available we want to fall back to the style hint.
+    // By creating a matching font descriptor we can verify whether the font
+    // is available or not, and avoid CTFontCreateWithFontDescriptor picking
+    // a default font for us based on incomplete information.
+    fontDescriptor = CTFontDescriptorCreateMatchingFontDescriptor(fontDescriptor, 0);
+    if (!fontDescriptor)
+        return nullptr;

-    QCFType<CFArrayRef> cascadeList = CFArrayRef(CTFontCopyDefaultCascadeListForLanguages(font,
-        (CFArrayRef)[NSUserDefaults.standardUserDefaults stringArrayForKey:@"AppleLanguages"]));
-    if (!cascadeList) {
-        qCWarning(lcQpaFonts) << "Failed to create fallback cascade list for" << family;
-        return QStringList();
-    }
+    return fallbacksForDescriptor(fontDescriptor);
+}

-    QStringList fallbackList;
-    const int numCascades = CFArrayGetCount(cascadeList);
-    for (int i = 0; i < numCascades; ++i) {
-        CTFontDescriptorRef fontFallback = CTFontDescriptorRef(CFArrayGetValueAtIndex(cascadeList, i));
-        QCFString fallbackFamilyName = CFStringRef(CTFontDescriptorCopyAttribute(fontFallback, kCTFontFamilyNameAttribute));
-        fallbackList.append(QString::fromCFString(fallbackFamilyName));
-    }
+CTFontDescriptorRef descriptorForFontType(CTFontUIFontType uiType)
+{
+    static const CGFloat kDefaultSizeForRequestedUIType = 0.0;
+    QCFType<CTFontRef> ctFont = CTFontCreateUIFontForLanguage(
+        uiType, kDefaultSizeForRequestedUIType, nullptr);
+    return CTFontCopyFontDescriptor(ctFont);
+}

-    return fallbackList;
+CTFontDescriptorRef descriptorForStyle(QFont::StyleHint styleHint)
+{
+    switch (styleHint) {
+        case QFont::SansSerif: return descriptorForFamily("Helvetica");
+        case QFont::Serif: return descriptorForFamily("Times New Roman");
+        case QFont::Monospace: return descriptorForFamily("Menlo");
+#ifdef Q_OS_MACOS
+        case QFont::Cursive: return descriptorForFamily("Apple Chancery");
+#endif
+        case QFont::Fantasy: return descriptorForFamily("Zapfino");
+        case QFont::TypeWriter: return descriptorForFamily("American Typewriter");
+        case QFont::AnyStyle: Q_FALLTHROUGH();
+        case QFont::System: return descriptorForFontType(kCTFontUIFontSystem);
+        default: return nullptr; // No matching font on this platform
+    }
 }

 QStringList QCoreTextFontDatabase::fallbacksForFamily(const QString &family, QFont::Style style, QFont::StyleHint styleHint, QChar::Script script) const
 {
    Q_UNUSED(style);

+    qCDebug(lcQpaFonts).nospace() << "Resolving fallbacks families for"
+        << (!family.isEmpty() ? qPrintable(QLatin1String(" family '%1' with").arg(family)) : "")
+        << " style hint " << styleHint;
+
    QMacAutoReleasePool pool;

-    QStringList fallbackList = fallbacksForFamily(family);
+    QStringList fallbackList;

-    if (fallbackList.isEmpty()) {
+    QCFType<CFArrayRef> fallbackFonts = fallbacksForFamily(family);
+    if (!fallbackFonts || !CFArrayGetCount(fallbackFonts)) {
        // We were not able to find a fallback for the specific family,
        // or the family was empty, so we fall back to the style hint.
-        QString styleFamily = [styleHint]{
-            switch (styleHint) {
-                case QFont::SansSerif: return QStringLiteral("Helvetica");
-                case QFont::Serif: return QStringLiteral("Times New Roman");
-                case QFont::Monospace: return QStringLiteral("Menlo");
-#ifdef Q_OS_MACOS
-                case QFont::Cursive: return QStringLiteral("Apple Chancery");
-#endif
-                case QFont::Fantasy: return QStringLiteral("Zapfino");
-                case QFont::TypeWriter: return QStringLiteral("American Typewriter");
-                case QFont::AnyStyle: Q_FALLTHROUGH();
-                case QFont::System: {
-                    QCFType<CTFontRef> font = CTFontCreateUIFontForLanguage(kCTFontUIFontSystem, 12.0, NULL);
-                    return static_cast<QString>(QCFString(CTFontCopyFullName(font)));
-                }
-                default: return QString(); // No matching font on this platform
-            }
-        }();
-        if (!styleFamily.isEmpty()) {
-            fallbackList = fallbacksForFamily(styleFamily);
-            if (!fallbackList.contains(styleFamily))
-                fallbackList.prepend(styleFamily);
+        if (!family.isEmpty())
+            qCDebug(lcQpaFonts) << "No fallbacks found. Using style hint instead";
+
+        if (QCFType<CTFontDescriptorRef> styleDescriptor = descriptorForStyle(styleHint)) {
+            CFMutableArrayRef tmp = CFArrayCreateMutable(kCFAllocatorDefault, 0, &kCFTypeArrayCallBacks);
+            CFArrayAppendValue(tmp, styleDescriptor);
+            QCFType<CFArrayRef> styleFallbacks = fallbacksForDescriptor(styleDescriptor);
+            CFArrayAppendArray(tmp, styleFallbacks, CFRangeMake(0, CFArrayGetCount(styleFallbacks)));
+            fallbackFonts = tmp;
        }
    }

-    if (fallbackList.isEmpty())
+    if (!fallbackFonts)
        return fallbackList;

-    // .Apple Symbols Fallback will be at the beginning of the list and we will
-    // detect that this has glyphs for Arabic and other writing systems.
-    // Since it is a symbol font, it should be the last resort, so that
-    // the proper fonts for these writing systems are preferred.
-    int symbolIndex = fallbackList.indexOf(QLatin1String(".Apple Symbols Fallback"));
-    if (symbolIndex >= 0)
-        fallbackList.move(symbolIndex, fallbackList.size() - 1);
+    const int numberOfFallbacks = CFArrayGetCount(fallbackFonts);
+    for (int i = 0; i < numberOfFallbacks; ++i) {
+        auto fallbackDescriptor = CTFontDescriptorRef(CFArrayGetValueAtIndex(fallbackFonts, i));
+        auto fallbackFamilyName = QCFString(CTFontDescriptorCopyAttribute(fallbackDescriptor, kCTFontFamilyNameAttribute));
+
+        if (!isFamilyPopulated(fallbackFamilyName)) {
+            // We need to populate, or at least register the fallback fonts,
+            // otherwise the Qt font database may not know they exist.
+            if (isPrivateFontFamily(fallbackFamilyName))
+                const_cast<QCoreTextFontDatabase *>(this)->populateFromDescriptor(fallbackDescriptor);
+            else
+                registerFontFamily(fallbackFamilyName);
+        }
+
+        fallbackList.append(fallbackFamilyName);
+    }
+
+    // Some fallback fonts will have have an order in the list returned
+    // by Core Text that would indicate they should be preferred for e.g.
+    // Arabic, or Emoji, while in reality only supporting a tiny subset
+    // of the required glyphs, or representing them by question marks.
+    // Move these to the end, so that the proper fonts are preferred.
+    for (const char *family : { ".Apple Symbols Fallback", ".Noto Sans Universal" }) {
+        int index = fallbackList.indexOf(QLatin1String(family));
+        if (index >= 0)
+            fallbackList.move(index, fallbackList.size() - 1);
+    }

 #if defined(Q_OS_MACOS)
    // Since we are only returning a list of default fonts for the current language, we do not
@ -529,18 +583,11 @@ QStringList QCoreTextFontDatabase::fallbacksForFamily(const QString &family, QFo
        fallbackList.append(QStringLiteral("Apple Symbols"));
 #endif

-    // Since iOS 13, the cascade list may contain meta-fonts which have not been
-    // populated to the database, such as ".AppleJapaneseFont". It is important that we
-    // include this in the fallback list, in order to get fallback support for all
-    // languages
-    for (const QString &fallback : fallbackList) {
-        if (!QPlatformFontDatabase::isFamilyPopulated(fallback))
-            const_cast<QCoreTextFontDatabase *>(this)->populateFamily(fallback);
-    }
-
    extern QStringList qt_sort_families_by_writing_system(QChar::Script, const QStringList &);
    fallbackList = qt_sort_families_by_writing_system(script, fallbackList);

+    qCDebug(lcQpaFonts).nospace() << "Fallback families ordered by script " << script << ": " << fallbackList;
+
    return fallbackList;
 }

@ -700,10 +747,8 @@ static CTFontDescriptorRef fontDescriptorFromTheme(QPlatformTheme::Font f)
    }
 #endif // Q_OS_IOS, Q_OS_TVOS, Q_OS_WATCHOS

-    // OSX default case and iOS fallback case
-    CTFontUIFontType fontType = fontTypeFromTheme(f);
-    QCFType<CTFontRef> ctFont = CTFontCreateUIFontForLanguage(fontType, 0.0, NULL);
-    return CTFontCopyFontDescriptor(ctFont);
+    // macOS default case and iOS fallback case
+    return descriptorForFontType(fontTypeFromTheme(f));
 }

 const QHash<QPlatformTheme::Font, QFont *> &QCoreTextFontDatabase::themeFonts() const
@ -736,8 +781,8 @@ QFont *QCoreTextFontDatabase::themeFont(QPlatformTheme::Font f) const
 QFont QCoreTextFontDatabase::defaultFont() const
 {
    if (defaultFontName.isEmpty()) {
-        QCFType<CTFontRef> font = CTFontCreateUIFontForLanguage(kCTFontUIFontSystem, 12.0, NULL);
-        defaultFontName = (QString) QCFString(CTFontCopyFullName(font));
+        QCFType<CTFontDescriptorRef> systemFont = descriptorForFontType(kCTFontUIFontSystem);
+        defaultFontName = QCFString(CTFontDescriptorCopyAttribute(systemFont, kCTFontFamilyNameAttribute));
    }

    return QFont(defaultFontName);
--- a/src/platformsupport/fontdatabases/mac/qcoretextfontdatabase_p.h
+++ b/src/platformsupport/fontdatabases/mac/qcoretextfontdatabase_p.h
@ -92,7 +92,7 @@ protected:

 private:
    void populateFromDescriptor(CTFontDescriptorRef font, const QString &familyName = QString());
-    static QStringList fallbacksForFamily(const QString &family);
+    static CFArrayRef fallbacksForFamily(const QString &family);

    mutable QString defaultFontName;

--- a/src/platformsupport/fontdatabases/windows/qwindowsfontdatabase.cpp
+++ b/src/platformsupport/fontdatabases/windows/qwindowsfontdatabase.cpp
@ -53,6 +53,7 @@
 #include <QtCore/QtEndian>
 #include <QtCore/QThreadStorage>
 #include <QtCore/private/qsystemlibrary_p.h>
+#include <QtCore/private/qwinregistry_p.h>

 #include <wchar.h>

@ -1210,33 +1211,8 @@ static int QT_WIN_CALLBACK populateFontFamilies(const LOGFONT *logFont, const TE

 void QWindowsFontDatabase::addDefaultEUDCFont()
 {
-    QString path;
-    {
-        HKEY key;
-        if (RegOpenKeyEx(HKEY_CURRENT_USER,
-                         L"EUDC\\1252",
-                         0,
-                         KEY_READ,
-                         &key) != ERROR_SUCCESS) {
-            return;
-        }
-
-        WCHAR value[MAX_PATH];
-        DWORD bufferSize = sizeof(value);
-        ZeroMemory(value, bufferSize);
-
-        if (RegQueryValueEx(key,
-                            L"SystemDefaultEUDCFont",
-                            nullptr,
-                            nullptr,
-                            reinterpret_cast<LPBYTE>(value),
-                            &bufferSize) == ERROR_SUCCESS) {
-            path = QString::fromWCharArray(value);
-        }
-
-        RegCloseKey(key);
-    }
-
+    const QString path = QWinRegistryKey(HKEY_CURRENT_USER, LR"(EUDC\1252)")
+                         .stringValue(L"SystemDefaultEUDCFont");
    if (!path.isEmpty()) {
        QFile file(path);
        if (!file.open(QIODevice::ReadOnly)) {
@ -2105,28 +2081,6 @@ int QWindowsFontDatabase::defaultVerticalDPI()
    return vDPI;
 }

-QString QWindowsFontDatabase::readRegistryString(HKEY parentHandle, const wchar_t *keyPath, const wchar_t *keyName)
-{
-    QString result;
-    HKEY handle = 0;
-    if (RegOpenKeyEx(parentHandle, keyPath, 0, KEY_READ, &handle) == ERROR_SUCCESS) {
-        // get the size and type of the value
-        DWORD dataType;
-        DWORD dataSize;
-        if (RegQueryValueEx(handle, keyName, 0, &dataType, 0, &dataSize) == ERROR_SUCCESS) {
-            if (dataType == REG_SZ || dataType == REG_EXPAND_SZ) {
-                dataSize += 2; // '\0' missing?
-                QVarLengthArray<unsigned char> data(dataSize);
-                data[dataSize - 2] = data[dataSize - 1] = '\0';
-                if (RegQueryValueEx(handle, keyName, 0, 0, data.data(), &dataSize) == ERROR_SUCCESS)
-                    result = QString::fromWCharArray(reinterpret_cast<const wchar_t *>(data.data()));
-            }
-        }
-        RegCloseKey(handle);
-    }
-    return result;
-}
-
 bool QWindowsFontDatabase::isPrivateFontFamily(const QString &family) const
 {
    return m_eudcFonts.contains(family) || QPlatformFontDatabase::isPrivateFontFamily(family);
--- a/src/platformsupport/fontdatabases/windows/qwindowsfontdatabase_p.h
+++ b/src/platformsupport/fontdatabases/windows/qwindowsfontdatabase_p.h
@ -133,8 +133,6 @@ public:
    static void setFontOptions(unsigned options);
    static unsigned fontOptions();

-    static QString readRegistryString(HKEY parentHandle, const wchar_t *keyPath, const wchar_t *keyName);
-
 private:
    void removeApplicationFonts();
    void addDefaultEUDCFont();
--- a/src/platformsupport/fontdatabases/windows/qwindowsfontenginedirectwrite.cpp
+++ b/src/platformsupport/fontdatabases/windows/qwindowsfontenginedirectwrite.cpp
@ -47,6 +47,7 @@
 #include <QtCore/QFile>
 #include <private/qstringiterator_p.h>
 #include <QtCore/private/qsystemlibrary_p.h>
+#include <QtCore/private/qwinregistry_p.h>
 #include <QtGui/private/qguiapplication_p.h>
 #include <qpa/qplatformintegration.h>
 #include <QtGui/private/qhighdpiscaling_p.h>
@ -945,10 +946,10 @@ void QWindowsFontEngineDirectWrite::initFontInfo(const QFontDef &request,

 QString QWindowsFontEngineDirectWrite::fontNameSubstitute(const QString &familyName)
 {
-    const wchar_t key[] = L"Software\\Microsoft\\Windows NT\\CurrentVersion\\FontSubstitutes";
    const QString substitute =
-        QWindowsFontDatabase::readRegistryString(HKEY_LOCAL_MACHINE, key,
-                                                 reinterpret_cast<const wchar_t *>(familyName.utf16()));
+        QWinRegistryKey(HKEY_LOCAL_MACHINE,
+                        LR"(Software\Microsoft\Windows NT\CurrentVersion\FontSubstitutes)")
+        .stringValue(familyName);
    return substitute.isEmpty() ? familyName : substitute;
 }

--- a/src/plugins/bearer/corewlan/qcorewlanengine.mm
+++ b/src/plugins/bearer/corewlan/qcorewlanengine.mm
@ -62,12 +62,11 @@ extern "C" { // Otherwise it won't find CWKeychain* symbols at link time
 #include <ifaddrs.h>

@interface QT_MANGLE_NAMESPACE(QNSListener) : NSObject <CWEventDelegate>
-
@property (assign) QCoreWlanEngine* engine;
-
@end
+QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSListener);

-@implementation QT_MANGLE_NAMESPACE(QNSListener) {
+@implementation QNSListener {
    NSNotificationCenter *notificationCenter;
    CWWiFiClient *client;
    QCoreWlanEngine *engine;
@ -88,7 +87,7 @@ extern "C" { // Otherwise it won't find CWKeychain* symbols at link time
    return self;
 }

-static QT_MANGLE_NAMESPACE(QNSListener) *listener = 0;
+static QNSListener *listener = 0;

 -(void)dealloc
 {
@ -415,7 +414,7 @@ void QCoreWlanEngine::initialize()
    QMacAutoReleasePool pool;

    if ([[CWWiFiClient interfaceNames] count] > 0 && !listener) {
-        listener = [[QT_MANGLE_NAMESPACE(QNSListener) alloc] init];
+        listener = [QNSListener alloc] init];
        listener.engine = this;
        hasWifi = true;
    } else {
--- a/src/plugins/platforms/cocoa/qcocoaaccessibility.h
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibility.h
@ -44,9 +44,9 @@
 #include <QtGui>
 #include <qpa/qplatformaccessibility.h>

-#ifndef QT_NO_ACCESSIBILITY
+#include "qcocoaaccessibilityelement.h"

-@class QT_MANGLE_NAMESPACE(QMacAccessibilityElement);
+#ifndef QT_NO_ACCESSIBILITY

 QT_BEGIN_NAMESPACE

@ -84,7 +84,7 @@ namespace QCocoaAccessible {
 NSString *macRole(QAccessibleInterface *interface);
 NSString *macSubrole(QAccessibleInterface *interface);
 bool shouldBeIgnored(QAccessibleInterface *interface);
-NSArray<QT_MANGLE_NAMESPACE(QMacAccessibilityElement) *> *unignoredChildren(QAccessibleInterface *interface);
+NSArray<QMacAccessibilityElement *> *unignoredChildren(QAccessibleInterface *interface);
 NSString *getTranslatedAction(const QString &qtAction);
 QString translateAction(NSString *nsAction, QAccessibleInterface *interface);
 bool hasValueAttribute(QAccessibleInterface *interface);
--- a/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.h
+++ b/src/plugins/platforms/cocoa/qcocoaaccessibilityelement.h
@ -50,8 +50,6 @@

 #import <qaccessible.h>

-@class QT_MANGLE_NAMESPACE(QMacAccessibilityElement);
-
@interface QT_MANGLE_NAMESPACE(QMacAccessibilityElement) : NSObject <NSAccessibilityElement>

 - (instancetype)initWithId:(QAccessible::Id)anId;
--- a/src/plugins/platforms/cocoa/qcocoaapplication.mm
+++ b/src/plugins/platforms/cocoa/qcocoaapplication.mm
@ -144,7 +144,7 @@ static void qt_maybeSendKeyEquivalentUpEvent(NSEvent *event)
    }
 }

-@implementation QT_MANGLE_NAMESPACE(QNSApplication)
+@implementation QNSApplication

 - (void)QT_MANGLE_NAMESPACE(qt_sendEvent_original):(NSEvent *)event
 {
@ -188,7 +188,7 @@ void qt_redirectNSApplicationSendEvent()
        // can be unloaded.
        return;

-    if ([NSApp isMemberOfClass:[QT_MANGLE_NAMESPACE(QNSApplication) class]]) {
+    if ([NSApp isMemberOfClass:[QNSApplication class]]) {
        // No need to change implementation since Qt
        // already controls a subclass of NSApplication
        return;
@ -201,7 +201,7 @@ void qt_redirectNSApplicationSendEvent()
    qt_cocoa_change_implementation(
            [NSApplication class],
            @selector(sendEvent:),
-            [QT_MANGLE_NAMESPACE(QNSApplication) class],
+            [QNSApplication class],
            @selector(QT_MANGLE_NAMESPACE(qt_sendEvent_replacement):),
            @selector(QT_MANGLE_NAMESPACE(qt_sendEvent_original):));
 }
--- a/src/plugins/platforms/cocoa/qcocoaapplicationdelegate.h
+++ b/src/plugins/platforms/cocoa/qcocoaapplicationdelegate.h
@ -89,8 +89,7 @@

 #include <qglobal.h>
 #include <private/qcore_mac_p.h>
-
-Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QCocoaNSMenuItem));
+#include "qcocoansmenu.h"

@interface QT_MANGLE_NAMESPACE(QCocoaApplicationDelegate) : NSObject <NSApplicationDelegate>
@property (nonatomic, retain) NSMenu *dockMenu;
@ -100,8 +99,9 @@ Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QCocoaNSMenuItem));
 - (bool)inLaunch;
@end

-@interface QT_MANGLE_NAMESPACE(QCocoaApplicationDelegate) (MenuAPI)
- (void)qt_itemFired:(QT_MANGLE_NAMESPACE(QCocoaNSMenuItem) *)item;
+QT_NAMESPACE_ALIAS_OBJC_CLASS(QCocoaApplicationDelegate);
+
+@interface QCocoaApplicationDelegate (MenuAPI)
+- (void)qt_itemFired:(QCocoaNSMenuItem *)item;
@end

-QT_NAMESPACE_ALIAS_OBJC_CLASS(QCocoaApplicationDelegate);
--- a/src/plugins/platforms/cocoa/qcocoaapplicationdelegate.mm
+++ b/src/plugins/platforms/cocoa/qcocoaapplicationdelegate.mm
@ -145,7 +145,7 @@ QT_USE_NAMESPACE
    [[NSApp mainMenu] cancelTracking];

    bool handle_quit = true;
-    NSMenuItem *quitMenuItem = [[QT_MANGLE_NAMESPACE(QCocoaMenuLoader) sharedMenuLoader] quitMenuItem];
+    NSMenuItem *quitMenuItem = [[QCocoaMenuLoader sharedMenuLoader] quitMenuItem];
    if (!QGuiApplicationPrivate::instance()->modalWindowList.isEmpty()
        && [quitMenuItem isEnabled]) {
        int visible = 0;
--- a/src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm
+++ b/src/plugins/platforms/cocoa/qcocoacolordialoghelper.mm
@ -293,7 +293,7 @@ class QCocoaColorPanel
 public:
    QCocoaColorPanel()
    {
-        mDelegate = [[QT_MANGLE_NAMESPACE(QNSColorPanelDelegate) alloc] init];
+        mDelegate = [[QNSColorPanelDelegate alloc] init];
    }

    ~QCocoaColorPanel()
@ -366,7 +366,7 @@ public:
    }

 private:
-    QT_MANGLE_NAMESPACE(QNSColorPanelDelegate) *mDelegate;
+    QNSColorPanelDelegate *mDelegate;
 };

 Q_GLOBAL_STATIC(QCocoaColorPanel, sharedColorPanel)
--- a/src/plugins/platforms/cocoa/qcocoafiledialoghelper.h
+++ b/src/plugins/platforms/cocoa/qcocoafiledialoghelper.h
@ -43,10 +43,16 @@
 #include <QObject>
 #include <QtWidgets/qtwidgetsglobal.h>
 #include <qpa/qplatformdialoghelper.h>
+#include <QtCore/private/qcore_mac_p.h>
+
+#import <AppKit/NSSavePanel.h>

 QT_REQUIRE_CONFIG(filedialog);

-Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QNSOpenSavePanelDelegate));
+@interface QT_MANGLE_NAMESPACE(QNSOpenSavePanelDelegate) : NSObject<NSOpenSavePanelDelegate>
+@end
+
+QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSOpenSavePanelDelegate);

 QT_BEGIN_NAMESPACE

@ -84,7 +90,7 @@ public:
    void QNSOpenSavePanelDelegate_filterSelected(int menuIndex);

 private:
-    QT_MANGLE_NAMESPACE(QNSOpenSavePanelDelegate) *mDelegate;
+    QNSOpenSavePanelDelegate *mDelegate;
    QUrl mDir;
 };

--- a/src/plugins/platforms/cocoa/qcocoafiledialoghelper.mm
+++ b/src/plugins/platforms/cocoa/qcocoafiledialoghelper.mm
@ -76,27 +76,6 @@ QT_USE_NAMESPACE

 typedef QSharedPointer<QFileDialogOptions> SharedPointerFileDialogOptions;

-@interface QT_MANGLE_NAMESPACE(QNSOpenSavePanelDelegate)
-    : NSObject<NSOpenSavePanelDelegate>
-
- (NSString *)strip:(const QString &)label;
- (BOOL)panel:(id)sender shouldEnableURL:(NSURL *)url;
- (void)filterChanged:(id)sender;
- (void)showModelessPanel;
- (BOOL)runApplicationModalPanel;
- (void)showWindowModalSheet:(QWindow *)docWidget;
- (void)updateProperties;
- (QStringList)acceptableExtensionsForSave;
- (QString)removeExtensions:(const QString &)filter;
- (void)createTextField;
- (void)createPopUpButton:(const QString &)selectedFilter hideDetails:(BOOL)hideDetails;
- (QStringList)findStrippedFilterWithVisualFilterName:(QString)name;
- (void)createAccessory;
-
-@end
-
-QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSOpenSavePanelDelegate);
-
@implementation QNSOpenSavePanelDelegate {
    @public
    NSOpenPanel *mOpenPanel;
--- a/src/plugins/platforms/cocoa/qcocoafontdialoghelper.mm
+++ b/src/plugins/platforms/cocoa/qcocoafontdialoghelper.mm
@ -283,7 +283,7 @@ class QCocoaFontPanel
 public:
    QCocoaFontPanel()
    {
-        mDelegate = [[QT_MANGLE_NAMESPACE(QNSFontPanelDelegate) alloc] init];
+        mDelegate = [[QNSFontPanelDelegate alloc] init];
    }

    ~QCocoaFontPanel()
@ -356,7 +356,7 @@ public:
    }

 private:
-    QT_MANGLE_NAMESPACE(QNSFontPanelDelegate) *mDelegate;
+    QNSFontPanelDelegate *mDelegate;
 };

 Q_GLOBAL_STATIC(QCocoaFontPanel, sharedFontPanel)
--- a/src/plugins/platforms/cocoa/qcocoamenu.h
+++ b/src/plugins/platforms/cocoa/qcocoamenu.h
@ -44,8 +44,7 @@
 #include <QtCore/QList>
 #include <qpa/qplatformmenu.h>
 #include "qcocoamenuitem.h"
-
-Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QCocoaNSMenu));
+#include "qcocoansmenu.h"

 QT_BEGIN_NAMESPACE

@ -107,7 +106,7 @@ private:
    void scheduleUpdate();

    QList<QCocoaMenuItem *> m_menuItems;
-    QT_MANGLE_NAMESPACE(QCocoaNSMenu) *m_nativeMenu;
+    QCocoaNSMenu *m_nativeMenu;
    NSMenuItem *m_attachedItem;
    int m_updateTimer;
    bool m_enabled:1;
--- a/src/plugins/platforms/cocoa/qcocoamenubar.mm
+++ b/src/plugins/platforms/cocoa/qcocoamenubar.mm
@ -278,12 +278,11 @@ void QCocoaMenuBar::updateMenuBarImmediately()
        // we still have to update the menubar.
        if ((win->flags() & Qt::WindowType_Mask) != Qt::Tool)
            return;
-        typedef QT_MANGLE_NAMESPACE(QCocoaApplicationDelegate) AppDelegate;
        NSApplication *app = [NSApplication sharedApplication];
-        if (![app.delegate isKindOfClass:[AppDelegate class]])
+        if (![app.delegate isKindOfClass:[QCocoaApplicationDelegate class]])
            return;
        // We apply this logic _only_ during the startup.
-        AppDelegate *appDelegate = app.delegate;
+        QCocoaApplicationDelegate *appDelegate = app.delegate;
        if (!appDelegate.inLaunch)
            return;
    }
@ -403,3 +402,4 @@ QCocoaWindow *QCocoaMenuBar::cocoaWindow() const

 QT_END_NAMESPACE

+#include "moc_qcocoamenubar.cpp"
--- a/src/plugins/platforms/cocoa/qcocoansmenu.h
+++ b/src/plugins/platforms/cocoa/qcocoansmenu.h
@ -59,31 +59,20 @@ QT_FORWARD_DECLARE_CLASS(QCocoaMenu);
 QT_FORWARD_DECLARE_CLASS(QCocoaMenuItem);

@interface QT_MANGLE_NAMESPACE(QCocoaNSMenuDelegate) : NSObject <NSMenuDelegate>
-
 + (instancetype)sharedMenuDelegate;
-
- (NSMenuItem *)findItemInMenu:(NSMenu *)menu
-                        forKey:(NSString *)key
-                     modifiers:(NSUInteger)modifiers;
-
+- (NSMenuItem *)findItemInMenu:(NSMenu *)menu forKey:(NSString *)key modifiers:(NSUInteger)modifiers;
@end

@interface QT_MANGLE_NAMESPACE(QCocoaNSMenu) : NSMenu
-
@property (readonly, nonatomic) QCocoaMenu *platformMenu;
-
 - (instancetype)initWithPlatformMenu:(QCocoaMenu *)menu;
-
@end

@interface QT_MANGLE_NAMESPACE(QCocoaNSMenuItem) : NSMenuItem
-
@property (nonatomic) QCocoaMenuItem *platformMenuItem;
-
 + (instancetype)separatorItemWithPlatformMenuItem:(QCocoaMenuItem *)menuItem;
 - (instancetype)initWithPlatformMenuItem:(QCocoaMenuItem *)menuItem;
 - (instancetype)init;
-
@end

 QT_NAMESPACE_ALIAS_OBJC_CLASS(QCocoaNSMenu);
--- a/src/plugins/platforms/cocoa/qcocoasystemtrayicon.mm
+++ b/src/plugins/platforms/cocoa/qcocoasystemtrayicon.mm
@ -80,6 +80,8 @@
 #include <qimagewriter.h>
 #include <qdebug.h>

+#include <QtCore/private/qcore_mac_p.h>
+
 #include "qcocoamenu.h"

 #include "qt_mac_p.h"
@ -92,8 +94,6 @@

 QT_USE_NAMESPACE

-@class QT_MANGLE_NAMESPACE(QNSImageView);
-
@interface QT_MANGLE_NAMESPACE(QNSStatusItem) : NSObject <NSUserNotificationCenterDelegate>
@property (nonatomic, assign) QCocoaMenu *menu;
@property (nonatomic, assign) QIcon icon;
@ -104,12 +104,13 @@ QT_USE_NAMESPACE
 - (void)doubleClickSelector:(id)sender;
@end

+QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSStatusItem);
+
@interface QT_MANGLE_NAMESPACE(QNSImageView) : NSImageView
@property (nonatomic, assign) BOOL down;
-@property (nonatomic, assign) QT_MANGLE_NAMESPACE(QNSStatusItem) *parent;
+@property (nonatomic, assign) QNSStatusItem *parent;
@end

-QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSStatusItem);
 QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSImageView);

 QT_BEGIN_NAMESPACE
@ -364,7 +365,7 @@ QT_END_NAMESPACE
@implementation QNSStatusItem {
    QCocoaSystemTrayIcon *systray;
    NSStatusItem *item;
-    QT_MANGLE_NAMESPACE(QNSImageView) *imageCell;
+    QNSImageView *imageCell;
 }

@synthesize menu = menu;
--- a/src/plugins/platforms/cocoa/qcocoatheme.h
+++ b/src/plugins/platforms/cocoa/qcocoatheme.h
@ -43,8 +43,6 @@
 #include <QtCore/QHash>
 #include <qpa/qplatformtheme.h>

-Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QCocoaThemeAppAppearanceObserver));
-
 #include <QtCore/private/qcore_mac_p.h>

 QT_BEGIN_NAMESPACE
--- a/src/plugins/platforms/cocoa/qnsview.h
+++ b/src/plugins/platforms/cocoa/qnsview.h
@ -51,37 +51,30 @@ class QCocoaGLContext;
 class QPointF;
 QT_END_NAMESPACE

-Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QNSViewMouseMoveHelper));
-Q_FORWARD_DECLARE_OBJC_CLASS(QT_MANGLE_NAMESPACE(QCocoaNSMenuItem));
-
@interface QT_MANGLE_NAMESPACE(QNSView) : NSView
-
@property (nonatomic, retain) NSCursor *cursor;
-
 - (instancetype)initWithCocoaWindow:(QCocoaWindow *)platformWindow;
-
 - (void)convertFromScreen:(NSPoint)mouseLocation toWindowPoint:(QPointF *)qtWindowPoint andScreenPoint:(QPointF *)qtScreenPoint;
-
-@end
-
-@interface QT_MANGLE_NAMESPACE(QNSView) (MouseAPI)
- (void)handleFrameStrutMouseEvent:(NSEvent *)theEvent;
- (void)resetMouseButtons;
-@end
-
-@interface QT_MANGLE_NAMESPACE(QNSView) (KeysAPI)
-+ (Qt::KeyboardModifiers)convertKeyModifiers:(ulong)modifierFlags;
-@end
-
-@interface QT_MANGLE_NAMESPACE(QNSView) (ComplexTextAPI)
- (void)unmarkText;
- (void)cancelComposingText;
-@end
-
-@interface QT_MANGLE_NAMESPACE(QNSView) (QtExtras)
-@property (nonatomic, readonly) QCocoaWindow *platformWindow;
@end

 QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSView);

+@interface QNSView (MouseAPI)
+- (void)handleFrameStrutMouseEvent:(NSEvent *)theEvent;
+- (void)resetMouseButtons;
+@end
+
+@interface QNSView (KeysAPI)
+ (Qt::KeyboardModifiers)convertKeyModifiers:(ulong)modifierFlags;
+@end
+
+@interface QNSView (ComplexTextAPI)
+- (void)unmarkText;
+- (void)cancelComposingText;
+@end
+
+@interface QNSView (QtExtras)
+@property (nonatomic, readonly) QCocoaWindow *platformWindow;
+@end
+
 #endif //QNSVIEW_H
--- a/src/plugins/platforms/cocoa/qnsview.mm
+++ b/src/plugins/platforms/cocoa/qnsview.mm
@ -66,13 +66,13 @@
 #include "qcocoaintegration.h"

 // Private interface
-@interface QT_MANGLE_NAMESPACE(QNSView) ()
+@interface QNSView ()
 - (BOOL)isTransparentForUserInput;
@property (assign) NSView* previousSuperview;
@property (assign) NSWindow* previousWindow;
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Drawing) <CALayerDelegate>
+@interface QNSView (Drawing) <CALayerDelegate>
 - (void)initDrawing;
@end

@ -84,7 +84,9 @@
 - (void)cursorUpdate:(NSEvent *)theEvent;
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Mouse)
+QT_NAMESPACE_ALIAS_OBJC_CLASS(QNSViewMouseMoveHelper);
+
+@interface QNSView (Mouse)
 - (void)initMouse;
 - (NSPoint)screenMousePoint:(NSEvent *)theEvent;
 - (void)mouseMovedImpl:(NSEvent *)theEvent;
@ -92,28 +94,28 @@
 - (void)mouseExitedImpl:(NSEvent *)theEvent;
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Touch)
+@interface QNSView (Touch)
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Tablet)
+@interface QNSView (Tablet)
 - (bool)handleTabletEvent:(NSEvent *)theEvent;
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Gestures)
+@interface QNSView (Gestures)
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Dragging)
+@interface QNSView (Dragging)
 -(void)registerDragTypes;
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (Keys)
+@interface QNSView (Keys)
@end

-@interface QT_MANGLE_NAMESPACE(QNSView) (ComplexText) <NSTextInputClient>
+@interface QNSView (ComplexText) <NSTextInputClient>
 - (void)textInputContextKeyboardSelectionDidChangeNotification:(NSNotification *)textInputContextKeyboardSelectionDidChangeNotification;
@end

-@implementation QT_MANGLE_NAMESPACE(QNSView) {
+@implementation QNSView {
    QPointer<QCocoaWindow> m_platformWindow;
    Qt::MouseButtons m_buttons;
    Qt::MouseButtons m_acceptedMouseDowns;
@ -125,7 +127,7 @@
    bool m_sendUpAsRightButton;
    Qt::KeyboardModifiers m_currentWheelModifiers;
    NSString *m_inputSource;
-    QT_MANGLE_NAMESPACE(QNSViewMouseMoveHelper) *m_mouseMoveHelper;
+    QNSViewMouseMoveHelper *m_mouseMoveHelper;
    bool m_resendKeyEvent;
    bool m_scrolling;
    bool m_updatingDrag;
@ -379,7 +381,7 @@

 // -----------------------------------------------------

-@implementation QT_MANGLE_NAMESPACE(QNSView) (QtExtras)
+@implementation QNSView (QtExtras)

 - (QCocoaWindow*)platformWindow
 {
--- a/src/plugins/platforms/cocoa/qnsview_accessibility.mm
+++ b/src/plugins/platforms/cocoa/qnsview_accessibility.mm
@ -47,7 +47,7 @@

 #import <AppKit/NSAccessibility.h>

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Accessibility)
+@implementation QNSView (Accessibility)

 - (id)childAccessibleElement
 {
--- a/src/plugins/platforms/cocoa/qnsview_complextext.mm
+++ b/src/plugins/platforms/cocoa/qnsview_complextext.mm
@ -39,7 +39,7 @@

 // This file is included from qnsview.mm, and only used to organize the code

-@implementation QT_MANGLE_NAMESPACE(QNSView) (ComplexTextAPI)
+@implementation QNSView (ComplexTextAPI)

 - (void)cancelComposingText
 {
@ -80,7 +80,7 @@

@end

-@implementation QT_MANGLE_NAMESPACE(QNSView) (ComplexText)
+@implementation QNSView (ComplexText)

 - (void)insertNewline:(id)sender
 {
--- a/src/plugins/platforms/cocoa/qnsview_dragging.mm
+++ b/src/plugins/platforms/cocoa/qnsview_dragging.mm
@ -39,7 +39,7 @@

 // This file is included from qnsview.mm, and only used to organize the code

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Dragging)
+@implementation QNSView (Dragging)

 -(void)registerDragTypes
 {
--- a/src/plugins/platforms/cocoa/qnsview_drawing.mm
+++ b/src/plugins/platforms/cocoa/qnsview_drawing.mm
@ -39,7 +39,7 @@

 // This file is included from qnsview.mm, and only used to organize the code

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Drawing)
+@implementation QNSView (Drawing)

 - (void)initDrawing
 {
--- a/src/plugins/platforms/cocoa/qnsview_gestures.mm
+++ b/src/plugins/platforms/cocoa/qnsview_gestures.mm
@ -43,7 +43,7 @@

 Q_LOGGING_CATEGORY(lcQpaGestures, "qt.qpa.input.gestures")

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Gestures)
+@implementation QNSView (Gestures)

 - (bool)handleGestureAsBeginEnd:(NSEvent *)event
 {
--- a/src/plugins/platforms/cocoa/qnsview_keys.mm
+++ b/src/plugins/platforms/cocoa/qnsview_keys.mm
@ -39,7 +39,7 @@

 // This file is included from qnsview.mm, and only used to organize the code

-@implementation QT_MANGLE_NAMESPACE(QNSView) (KeysAPI)
+@implementation QNSView (KeysAPI)

 + (Qt::KeyboardModifiers)convertKeyModifiers:(ulong)modifierFlags
 {
@ -60,7 +60,7 @@

@end

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Keys)
+@implementation QNSView (Keys)

 - (int)convertKeyCode:(QChar)keyChar
 {
--- a/src/plugins/platforms/cocoa/qnsview_menus.mm
+++ b/src/plugins/platforms/cocoa/qnsview_menus.mm
@ -53,11 +53,11 @@ static bool selectorIsCutCopyPaste(SEL selector)
            || selector == @selector(selectAll:));
 }

-@interface QT_MANGLE_NAMESPACE(QNSView) (Menus)
+@interface QNSView (Menus)
 - (void)qt_itemFired:(QCocoaNSMenuItem *)item;
@end

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Menus)
+@implementation QNSView (Menus)

 - (BOOL)validateMenuItem:(NSMenuItem*)item
 {
--- a/src/plugins/platforms/cocoa/qnsview_mouse.mm
+++ b/src/plugins/platforms/cocoa/qnsview_mouse.mm
@ -55,7 +55,7 @@
    interact with the responder chain by e.g. calling super if Qt does not
    accept the mouse event
 */
-@implementation QT_MANGLE_NAMESPACE(QNSViewMouseMoveHelper) {
+@implementation QNSViewMouseMoveHelper {
    QNSView *view;
 }

@ -89,7 +89,7 @@

@end

-@implementation QT_MANGLE_NAMESPACE(QNSView) (MouseAPI)
+@implementation QNSView (MouseAPI)

 - (void)resetMouseButtons
 {
@ -178,7 +178,7 @@
 }
@end

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Mouse)
+@implementation QNSView (Mouse)

 - (void)initMouse
 {
@ -193,7 +193,7 @@
    m_dontOverrideCtrlLMB = qt_mac_resolveOption(false, m_platformWindow->window(),
            "_q_platform_MacDontOverrideCtrlLMB", "QT_MAC_DONT_OVERRIDE_CTRL_LMB");

-    m_mouseMoveHelper = [[QT_MANGLE_NAMESPACE(QNSViewMouseMoveHelper) alloc] initWithView:self];
+    m_mouseMoveHelper = [[QNSViewMouseMoveHelper alloc] initWithView:self];

    NSUInteger trackingOptions = NSTrackingActiveInActiveApp
        | NSTrackingMouseEnteredAndExited | NSTrackingCursorUpdate;
--- a/src/plugins/platforms/cocoa/qnsview_tablet.mm
+++ b/src/plugins/platforms/cocoa/qnsview_tablet.mm
@ -54,7 +54,7 @@ struct QCocoaTabletDeviceData
 typedef QHash<uint, QCocoaTabletDeviceData> QCocoaTabletDeviceDataHash;
 Q_GLOBAL_STATIC(QCocoaTabletDeviceDataHash, tabletDeviceDataHash)

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Tablet)
+@implementation QNSView (Tablet)

 - (bool)handleTabletEvent:(NSEvent *)theEvent
 {
--- a/src/plugins/platforms/cocoa/qnsview_touch.mm
+++ b/src/plugins/platforms/cocoa/qnsview_touch.mm
@ -41,7 +41,7 @@

 Q_LOGGING_CATEGORY(lcQpaTouch, "qt.qpa.input.touch")

-@implementation QT_MANGLE_NAMESPACE(QNSView) (Touch)
+@implementation QNSView (Touch)

 - (bool)shouldSendSingleTouch
 {
--- a/src/plugins/platforms/cocoa/qprintengine_mac_p.h
+++ b/src/plugins/platforms/cocoa/qprintengine_mac_p.h
@ -64,11 +64,7 @@

 #include "qpaintengine_mac_p.h"

-#ifdef __OBJC__
-@class NSPrintInfo;
-#else
-typedef void NSPrintInfo;
-#endif
+Q_FORWARD_DECLARE_OBJC_CLASS(NSPrintInfo);

 QT_BEGIN_NAMESPACE

--- a/src/plugins/platforms/windows/qwindowscontext.cpp
+++ b/src/plugins/platforms/windows/qwindowscontext.cpp
@ -79,6 +79,7 @@
 #include <QtCore/qscopedpointer.h>
 #include <QtCore/quuid.h>
 #include <QtCore/private/qsystemlibrary_p.h>
+#include <QtCore/private/qwinregistry_p.h>

 #include <QtEventDispatcherSupport/private/qwindowsguieventdispatcher_p.h>

@ -1518,28 +1519,13 @@ QTouchDevice *QWindowsContext::touchDevice() const
        d->m_pointerHandler.touchDevice() : d->m_mouseHandler.touchDevice();
 }

-static DWORD readDwordRegistrySetting(const wchar_t *regKey, const wchar_t *subKey, DWORD defaultValue)
-{
-    DWORD result = defaultValue;
-    HKEY handle;
-    if (RegOpenKeyEx(HKEY_CURRENT_USER, regKey, 0, KEY_READ, &handle) == ERROR_SUCCESS) {
-        DWORD type;
-        if (RegQueryValueEx(handle, subKey, nullptr, &type, nullptr, nullptr) == ERROR_SUCCESS
-            && type == REG_DWORD) {
-            DWORD value;
-            DWORD size = sizeof(result);
-            if (RegQueryValueEx(handle, subKey, nullptr, nullptr, reinterpret_cast<unsigned char *>(&value), &size) == ERROR_SUCCESS)
-                result = value;
-        }
-        RegCloseKey(handle);
-    }
-    return result;
-}
-
 DWORD QWindowsContext::readAdvancedExplorerSettings(const wchar_t *subKey, DWORD defaultValue)
 {
-    return readDwordRegistrySetting(L"Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Advanced",
-                                    subKey, defaultValue);
+    const auto value =
+        QWinRegistryKey(HKEY_CURRENT_USER,
+                        LR"(Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced)")
+                       .dwordValue(subKey);
+    return value.second ? value.first : defaultValue;
 }

 static inline bool isEmptyRect(const RECT &rect)
--- a/src/plugins/platforms/windows/qwindowsservices.cpp
+++ b/src/plugins/platforms/windows/qwindowsservices.cpp
@ -45,6 +45,8 @@
 #include <QtCore/qdebug.h>
 #include <QtCore/qdir.h>

+#include <QtCore/private/qwinregistry_p.h>
+
 #include <shlobj.h>
 #include <intshcut.h>

@ -78,35 +80,24 @@ static inline QString mailCommand()

    const wchar_t mailUserKey[] = L"Software\\Microsoft\\Windows\\Shell\\Associations\\UrlAssociations\\mailto\\UserChoice";

-    wchar_t command[MAX_PATH] = {0};
    // Check if user has set preference, otherwise use default.
-    HKEY handle;
-    QString keyName;
-    if (!RegOpenKeyEx(HKEY_CURRENT_USER, mailUserKey, 0, KEY_READ, &handle)) {
-        DWORD bufferSize = BufferSize;
-        if (!RegQueryValueEx(handle, L"Progid", nullptr, nullptr, reinterpret_cast<unsigned char*>(command), &bufferSize))
-            keyName = QString::fromWCharArray(command);
-        RegCloseKey(handle);
-    }
+    QString keyName = QWinRegistryKey(HKEY_CURRENT_USER, mailUserKey)
+                      .stringValue( L"Progid");
    const QLatin1String mailto = keyName.isEmpty() ? QLatin1String("mailto") : QLatin1String();
    keyName += mailto + QLatin1String("\\Shell\\Open\\Command");
    if (debug)
        qDebug() << __FUNCTION__ << "keyName=" << keyName;
-    command[0] = 0;
-    if (!RegOpenKeyExW(HKEY_CLASSES_ROOT, reinterpret_cast<const wchar_t*>(keyName.utf16()), 0, KEY_READ, &handle)) {
-        DWORD bufferSize = BufferSize;
-        RegQueryValueEx(handle, L"", nullptr, nullptr, reinterpret_cast<unsigned char*>(command), &bufferSize);
-        RegCloseKey(handle);
-    }
+    const QString command = QWinRegistryKey(HKEY_CLASSES_ROOT, keyName).stringValue(L"");
    // QTBUG-57816: As of Windows 10, if there is no mail client installed, an entry like
    // "rundll32.exe .. url.dll,MailToProtocolHandler %l" is returned. Launching it
    // silently fails or brings up a broken dialog after a long time, so exclude it and
    // fall back to ShellExecute() which brings up the URL assocation dialog.
-    if (!command[0] || wcsstr(command, L",MailToProtocolHandler") != nullptr)
+    if (command.isEmpty() || command.contains(QLatin1String(",MailToProtocolHandler")))
        return QString();
    wchar_t expandedCommand[MAX_PATH] = {0};
-    return ExpandEnvironmentStrings(command, expandedCommand, MAX_PATH) ?
-           QString::fromWCharArray(expandedCommand) : QString::fromWCharArray(command);
+    return ExpandEnvironmentStrings(reinterpret_cast<const wchar_t *>(command.utf16()),
+                                    expandedCommand, MAX_PATH)
+        ? QString::fromWCharArray(expandedCommand) : command;
 }

 static inline bool launchMail(const QUrl &url)
--- a/src/tools/bootstrap/bootstrap.pro
+++ b/src/tools/bootstrap/bootstrap.pro
@ -126,6 +126,7 @@ win32:SOURCES += ../../corelib/global/qoperatingsystemversion_win.cpp \
                 ../../corelib/kernel/qsharedmemory_win.cpp \
                 ../../corelib/kernel/qsystemsemaphore_win.cpp \
                 ../../corelib/plugin/qsystemlibrary.cpp \
+                 ../../corelib/kernel/qwinregistry.cpp \

 mac {
    SOURCES += \
--- a/src/widgets/kernel/qdesktopwidget.cpp
+++ b/src/widgets/kernel/qdesktopwidget.cpp
@ -211,7 +211,9 @@ QDesktopWidget::QDesktopWidget()
    setObjectName(QLatin1String("desktop"));
    d->_q_updateScreens();
    connect(qApp, SIGNAL(screenAdded(QScreen*)), this, SLOT(_q_updateScreens()));
+#if QT_DEPRECATED_SINCE(5, 11)
    connect(qApp, SIGNAL(primaryScreenChanged(QScreen*)), this, SIGNAL(primaryScreenChanged()));
+#endif
 }

 QDesktopWidget::~QDesktopWidget()
--- a/src/widgets/kernel/qwidget.cpp
+++ b/src/widgets/kernel/qwidget.cpp
@ -2914,6 +2914,8 @@ void QWidget::setWindowState(Qt::WindowStates newstate)
 {
    Q_D(QWidget);
    Qt::WindowStates oldstate = windowState();
+    if (newstate.testFlag(Qt::WindowMinimized)) // QTBUG-46763
+       newstate.setFlag(Qt::WindowActive, false);
    if (oldstate == newstate)
        return;
    if (isWindow() && !testAttribute(Qt::WA_WState_Created))
--- a/src/widgets/styles/qstylesheetstyle.cpp
+++ b/src/widgets/styles/qstylesheetstyle.cpp
@ -5035,6 +5035,14 @@ QSize QStyleSheetStyle::sizeFromContents(ContentsType ct, const QStyleOption *op
                QRenderRule subRule = renderRule(w, opt, PseudoElement_HeaderViewSection);
                if (subRule.hasGeometry() || subRule.hasBox() || !subRule.hasNativeBorder() || subRule.hasFont) {
                    sz = subRule.adjustSize(csz);
+                    if (!sz.isValid()) {
+                        // Try to set the missing values based on the base style.
+                        const auto baseSize = baseStyle()->sizeFromContents(ct, opt, sz, w);
+                        if (sz.width() < 0)
+                            sz.setWidth(baseSize.width());
+                        if (sz.height() < 0)
+                            sz.setHeight(baseSize.height());
+                    }
                    if (!subRule.hasGeometry()) {
                        QSize nativeContentsSize;
                        bool nullIcon = hdr->icon.isNull();
--- a/src/widgets/util/qscroller.cpp
+++ b/src/widgets/util/qscroller.cpp
@ -1031,7 +1031,8 @@ void QScrollerPrivate::setDpi(const QPointF &dpi)
 */
 void QScrollerPrivate::setDpiFromWidget(QWidget *widget)
 {
-    const QScreen *screen = QGuiApplication::screens().at(QApplication::desktop()->screenNumber(widget));
+    const QScreen *screen = widget ? widget->screen() : QGuiApplication::primaryScreen();
+    Q_ASSERT(screen);
    setDpi(QPointF(screen->physicalDotsPerInchX(), screen->physicalDotsPerInchY()));
 }

--- a/src/widgets/widgets/qeffects.cpp
+++ b/src/widgets/widgets/qeffects.cpp
@ -99,7 +99,7 @@ static QAlphaWidget* q_blend = 0;
  Constructs a QAlphaWidget.
 */
 QT_WARNING_PUSH
-QT_WARNING_DISABLE_DEPRECATED // QDesktopWidget::screen()
+QT_WARNING_DISABLE_DEPRECATED // ### Qt 6: Find a replacement for QDesktopWidget::screen()
 QAlphaWidget::QAlphaWidget(QWidget* w, Qt::WindowFlags f)
    : QWidget(QApplication::desktop()->screen(QDesktopWidgetPrivate::screenNumber(w)), f)
 {
--- a/tests/auto/corelib/global/global.pro
+++ b/tests/auto/corelib/global/global.pro
@ -12,3 +12,6 @@ SUBDIRS=\
    qtendian \
    qglobalstatic \
    qhooks
+
+win32:!winrt: SUBDIRS += \
+    qwinregistry
--- a/tests/auto/corelib/global/qwinregistry/qwinregistry.pro
+++ b/tests/auto/corelib/global/qwinregistry/qwinregistry.pro
@ -0,0 +1,8 @@
+CONFIG   += testcase
+QT       += testlib core-private
+QT       -= gui
+
+TARGET = tst_qwinregistry
+CONFIG   += console
+
+SOURCES += tst_qwinregistry.cpp
--- a/tests/auto/corelib/global/qwinregistry/tst_qwinregistry.cpp
+++ b/tests/auto/corelib/global/qwinregistry/tst_qwinregistry.cpp
@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** 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 General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** 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-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtTest/QtTest>
+
+#include <QtCore/qoperatingsystemversion.h>
+
+#include <QtCore/private/qwinregistry_p.h>
+
+class tst_QWinRegistry : public QObject
+{
+    Q_OBJECT
+
+public Q_SLOTS:
+    void initTestCase();
+
+private Q_SLOTS:
+    void values();
+};
+
+void tst_QWinRegistry::initTestCase()
+{
+    if (QOperatingSystemVersion::current() < QOperatingSystemVersion::Windows10)
+        QSKIP("This test requires registry values present in Windows 10");
+}
+
+void tst_QWinRegistry::values()
+{
+    QWinRegistryKey key(HKEY_LOCAL_MACHINE, LR"(SOFTWARE\Microsoft\Windows NT\CurrentVersion)");
+    QVERIFY(key.isValid());
+    QVERIFY(!key.stringValue(L"ProductName").isEmpty());
+    QVERIFY(key.stringValue(L"NonExistingKey").isEmpty());
+    auto majorVersion = key.dwordValue(L"CurrentMajorVersionNumber");
+    QVERIFY(majorVersion.second);
+    QVERIFY(majorVersion.first > 0);
+    auto nonExistingValue = key.dwordValue(L"NonExistingKey");
+    QVERIFY(!nonExistingValue.second);
+    QCOMPARE(nonExistingValue.first, 0u);
+}
+
+QTEST_APPLESS_MAIN(tst_QWinRegistry);
+
+#include "tst_qwinregistry.moc"
--- a/tests/auto/corelib/io/qfileinfo/tst_qfileinfo.cpp
+++ b/tests/auto/corelib/io/qfileinfo/tst_qfileinfo.cpp
@ -49,6 +49,7 @@
 #ifdef Q_OS_WIN
 #include <qt_windows.h>
 #if !defined(Q_OS_WINRT)
+#include <private/qwinregistry_p.h>
 #include <lm.h>
 #endif
 #endif
@ -1243,17 +1244,12 @@ void tst_QFileInfo::fileTimes()
    //In Vista the last-access timestamp is not updated when the file is accessed/touched (by default).
    //To enable this the HKLM\SYSTEM\CurrentControlSet\Control\FileSystem\NtfsDisableLastAccessUpdate
    //is set to 0, in the test machine.
-    HKEY key;
-    if (ERROR_SUCCESS == RegOpenKeyEx(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\FileSystem",
-        0, KEY_READ, &key)) {
-            DWORD disabledAccessTimes = 0;
-            DWORD size = sizeof(DWORD);
-            LONG error = RegQueryValueEx(key, L"NtfsDisableLastAccessUpdate"
-                , NULL, NULL, (LPBYTE)&disabledAccessTimes, &size);
-            if (ERROR_SUCCESS == error && disabledAccessTimes)
-                noAccessTime = true;
-            RegCloseKey(key);
-    }
+    const auto disabledAccessTimes =
+        QWinRegistryKey(HKEY_LOCAL_MACHINE,
+                        LR"(SYSTEM\CurrentControlSet\Control\FileSystem)")
+        .dwordValue(L"NtfsDisableLastAccessUpdate");
+    if (disabledAccessTimes.second && disabledAccessTimes.first != 0)
+        noAccessTime = true;
 #endif

    if (noAccessTime)
--- a/tests/auto/corelib/io/qsettings/tst_qsettings.cpp
+++ b/tests/auto/corelib/io/qsettings/tst_qsettings.cpp
@ -54,6 +54,9 @@

 #if defined(Q_OS_WIN)
 #include <QtCore/qt_windows.h>
+#ifndef Q_OS_WINRT
+#  include <private/qwinregistry_p.h>
+#endif
 #else
 #include <unistd.h>
 #endif
@ -3623,16 +3626,13 @@ void tst_QSettings::recursionBug()

 #if defined(Q_OS_WIN) && !defined(Q_OS_WINRT)

-static DWORD readKeyType(HKEY handle, const QString &rSubKey)
+static DWORD readKeyType(HKEY handle, QStringView rSubKey)
 {
    DWORD dataType;
    DWORD dataSize;
-    LONG res = RegQueryValueEx(handle, reinterpret_cast<const wchar_t *>(rSubKey.utf16()), 0, &dataType, 0, &dataSize);
-
-    if (res == ERROR_SUCCESS)
-        return dataType;
-
-    return 0;
+    LONG res = RegQueryValueEx(handle, reinterpret_cast<const wchar_t *>(rSubKey.utf16()),
+                               nullptr, &dataType, nullptr, &dataSize);
+    return res == ERROR_SUCCESS ? dataType : 0;
 }

 // This is a regression test for QTBUG-13249, where QSettings was storing
@ -3652,29 +3652,12 @@ void tst_QSettings::consistentRegistryStorage()
    QCOMPARE(settings1.value("quint64_value").toULongLong(), (quint64)1024);
    settings1.sync();

-    HKEY handle;
-    LONG res;
-    QString keyName = "Software\\software.org\\KillerAPP";
-    res = RegOpenKeyEx(HKEY_CURRENT_USER, reinterpret_cast<const wchar_t *>(keyName.utf16()), 0, KEY_READ, &handle);
-    if (res == ERROR_SUCCESS)
-    {
-        DWORD dataType;
-        dataType = readKeyType(handle, QString("qint32_value"));
-        if (dataType != 0) {
-            QCOMPARE((int)REG_DWORD, (int)dataType);
-        }
-        dataType = readKeyType(handle, QString("quint32_value"));
-        if (dataType != 0) {
-            QCOMPARE((int)REG_DWORD, (int)dataType);
-        }
-        dataType = readKeyType(handle, QString("qint64_value"));
-        if (dataType != 0) {
-            QCOMPARE((int)REG_QWORD, (int)dataType);
-        }
-        dataType = readKeyType(handle, QString("quint64_value"));
-        if (dataType != 0) {
-            QCOMPARE((int)REG_QWORD, (int)dataType);
-        }
+    QWinRegistryKey handle(HKEY_CURRENT_USER, LR"(Software\software.org\KillerAPP)");
+    if (handle.isValid()) {
+        QCOMPARE(readKeyType(handle, L"qint32_value"), DWORD(REG_DWORD));
+        QCOMPARE(readKeyType(handle, L"quint32_value"), DWORD(REG_DWORD));
+        QCOMPARE(readKeyType(handle, L"qint64_value"), DWORD(REG_QWORD));
+        QCOMPARE(readKeyType(handle, L"quint64_value"), DWORD(REG_QWORD));
        RegCloseKey(handle);
    }
 }
--- a/tests/auto/gui/kernel/qtouchevent/tst_qtouchevent.cpp
+++ b/tests/auto/gui/kernel/qtouchevent/tst_qtouchevent.cpp
@ -26,7 +26,7 @@
 **
 ****************************************************************************/

-#include <QtWidgets/QDesktopWidget>
+#include <QtGui/QScreen>
 #include <QtWidgets/QGraphicsItem>
 #include <QtWidgets/QGraphicsScene>
 #include <QtWidgets/QGraphicsView>
@ -617,7 +617,7 @@ void tst_QTouchEvent::basicRawEventTranslation()
    QPointF pos = touchWidget.rect().center();
    QPointF screenPos = touchWidget.mapToGlobal(pos.toPoint());
    QPointF delta(10, 10);
-    QRectF screenGeometry = QApplication::desktop()->screenGeometry(&touchWidget);
+    QRectF screenGeometry = touchWidget.screen()->geometry();

    QTouchEvent::TouchPoint rawTouchPoint;
    rawTouchPoint.setId(0);
@ -753,7 +753,7 @@ void tst_QTouchEvent::multiPointRawEventTranslationOnTouchScreen()
    QPointF leftScreenPos = leftWidget.mapToGlobal(leftPos.toPoint());
    QPointF rightScreenPos = rightWidget.mapToGlobal(rightPos.toPoint());
    QPointF centerScreenPos = touchWidget.mapToGlobal(centerPos.toPoint());
-    QRectF screenGeometry = QApplication::desktop()->screenGeometry(&touchWidget);
+    QRectF screenGeometry = touchWidget.screen()->geometry();

    QList<QTouchEvent::TouchPoint> rawTouchPoints;
    rawTouchPoints.append(QTouchEvent::TouchPoint(0));
@ -968,7 +968,7 @@ void tst_QTouchEvent::touchOnMultipleTouchscreens()
    QPointF pos = touchWidget.rect().center();
    QPointF screenPos = touchWidget.mapToGlobal(pos.toPoint());
    QPointF delta(10, 10);
-    QRectF screenGeometry = QApplication::desktop()->screenGeometry(&touchWidget);
+    QRectF screenGeometry = touchWidget.screen()->geometry();

    QVector<QTouchEvent::TouchPoint> rawTouchPoints(3);
    rawTouchPoints[0].setId(0);
@ -1131,7 +1131,7 @@ void tst_QTouchEvent::multiPointRawEventTranslationOnTouchPad()
    QPointF leftScreenPos = leftWidget.mapToGlobal(leftPos.toPoint());
    QPointF rightScreenPos = rightWidget.mapToGlobal(rightPos.toPoint());
    QPointF centerScreenPos = touchWidget.mapToGlobal(centerPos.toPoint());
-    QRectF screenGeometry = QApplication::desktop()->screenGeometry(&touchWidget);
+    QRectF screenGeometry = touchWidget.screen()->geometry();

    QList<QTouchEvent::TouchPoint> rawTouchPoints;
    rawTouchPoints.append(QTouchEvent::TouchPoint(0));
@ -1348,7 +1348,7 @@ void tst_QTouchEvent::basicRawEventTranslationOfIds()
        screenPos << touchWidget.mapToGlobal(pos[i].toPoint());
    }
    QPointF delta(10, 10);
-    QRectF screenGeometry = QApplication::desktop()->screenGeometry(&touchWidget);
+    QRectF screenGeometry = touchWidget.screen()->geometry();

    QVector<QPointF> rawPosList;
    rawPosList << QPointF(12, 34) << QPointF(56, 78);
@ -1629,7 +1629,7 @@ void tst_QTouchEvent::deleteInRawEventTranslation()
    QPointF leftScreenPos = leftWidget->mapToGlobal(leftPos.toPoint());
    QPointF centerScreenPos = centerWidget->mapToGlobal(centerPos.toPoint());
    QPointF rightScreenPos = rightWidget->mapToGlobal(rightPos.toPoint());
-    QRectF screenGeometry = QApplication::desktop()->screenGeometry(&touchWidget);
+    QRectF screenGeometry = touchWidget.screen()->geometry();

    QList<QTouchEvent::TouchPoint> rawTouchPoints;
    rawTouchPoints.append(QTouchEvent::TouchPoint(0));
--- a/tests/auto/widgets/graphicsview/qgraphicsitem/tst_qgraphicsitem.cpp
+++ b/tests/auto/widgets/graphicsview/qgraphicsitem/tst_qgraphicsitem.cpp
@ -11084,7 +11084,7 @@ static QList<QTouchEvent::TouchPoint>
    tp.setStartScreenPos(screenPos);
    tp.setLastScreenPos(screenPos);
    tp.setEllipseDiameters(ellipseDiameters);
-    const QSizeF screenSize = QApplication::desktop()->screenGeometry(&view).size();
+    const QSizeF screenSize = view.screen()->geometry().size();
    tp.setNormalizedPos(QPointF(screenPos.x() / screenSize.width(), screenPos.y() / screenSize.height()));
    return QList<QTouchEvent::TouchPoint>() << tp;
 }
--- a/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
+++ b/tests/auto/widgets/itemviews/qheaderview/tst_qheaderview.cpp
@ -215,6 +215,7 @@ private slots:
    void QTBUG14242_hideSectionAutoSize();
    void QTBUG50171_visualRegionForSwappedItems();
    void QTBUG53221_assertShiftHiddenRow();
+    void QTBUG75615_sizeHintWithStylesheet();
    void ensureNoIndexAtLength();
    void offsetConsistent();

@ -2557,6 +2558,26 @@ void tst_QHeaderView::QTBUG53221_assertShiftHiddenRow()
    QCOMPARE(tableView.verticalHeader()->isSectionHidden(2), true);
 }

+void tst_QHeaderView::QTBUG75615_sizeHintWithStylesheet()
+{
+    QTableView tableView;
+    QStandardItemModel model(1, 1);
+    tableView.setModel(&model);
+    tableView.show();
+
+    const auto headerView = tableView.horizontalHeader();
+    const auto oldSizeHint = headerView->sizeHint();
+    QVERIFY(oldSizeHint.isValid());
+
+    tableView.setStyleSheet("QTableView QHeaderView::section { height: 100px;}");
+    QCOMPARE(headerView->sizeHint().width(), oldSizeHint.width());
+    QCOMPARE(headerView->sizeHint().height(), 100);
+
+    tableView.setStyleSheet("QTableView QHeaderView::section { width: 100px;}");
+    QCOMPARE(headerView->sizeHint().height(), oldSizeHint.height());
+    QCOMPARE(headerView->sizeHint().width(), 100);
+}
+
 void protected_QHeaderView::testVisualRegionForSelection()
 {
    QRegion r = visualRegionForSelection(QItemSelection(model()->index(1, 0), model()->index(1, 2)));
--- a/tests/auto/widgets/kernel/qdesktopwidget/tst_qdesktopwidget.cpp
+++ b/tests/auto/widgets/kernel/qdesktopwidget/tst_qdesktopwidget.cpp
@ -42,10 +42,12 @@ class tst_QDesktopWidget : public QObject
 private slots:
    void cleanup();

+#if QT_DEPRECATED_SINCE(5, 11)
    void numScreens();
    void primaryScreen();
-    void screenNumberForQWidget();
    void screenNumberForQPoint();
+#endif
+    void screenNumberForQWidget();
    void availableGeometry();
    void screenGeometry();
    void topLevels();
@ -56,6 +58,7 @@ void tst_QDesktopWidget::cleanup()
    QVERIFY(QApplication::topLevelWidgets().isEmpty());
 }

+#if QT_DEPRECATED_SINCE(5, 11)
 void tst_QDesktopWidget::numScreens()
 {
    QDesktopWidget desktop;
@ -68,14 +71,17 @@ void tst_QDesktopWidget::primaryScreen()
    QVERIFY(desktop.primaryScreen() >= 0);
    QVERIFY(desktop.primaryScreen() < desktop.numScreens());
 }
+#endif

 void tst_QDesktopWidget::availableGeometry()
 {
    QDesktopWidget desktop;
    QTest::ignoreMessage(QtWarningMsg, "QDesktopWidget::availableGeometry(): Attempt "
                                       "to get the available geometry of a null widget");
-    desktop.availableGeometry((QWidget *)0);
+    QRect r = desktop.availableGeometry(nullptr);
+    QVERIFY(r.isNull());

+#if QT_DEPRECATED_SINCE(5, 11)
    QRect total;
    QRect available;

@ -90,13 +96,14 @@ void tst_QDesktopWidget::availableGeometry()
    QVERIFY(total.contains(available));
    QCOMPARE(desktop.availableGeometry(desktop.primaryScreen()), available);
    QCOMPARE(desktop.screenGeometry(desktop.primaryScreen()), total);
+#endif
 }

 void tst_QDesktopWidget::screenNumberForQWidget()
 {
    QDesktopWidget desktop;

-    QCOMPARE(desktop.screenNumber(0), 0);
+    QCOMPARE(desktop.screenNumber(nullptr), 0);

    QWidget widget;
    widget.show();
@ -105,9 +112,10 @@ void tst_QDesktopWidget::screenNumberForQWidget()

    int widgetScreen = desktop.screenNumber(&widget);
    QVERIFY(widgetScreen > -1);
-    QVERIFY(widgetScreen < desktop.numScreens());
+    QVERIFY(widgetScreen < QGuiApplication::screens().size());
 }

+#if QT_DEPRECATED_SINCE(5, 11)
 void tst_QDesktopWidget::screenNumberForQPoint()
 {
    // make sure QDesktopWidget::screenNumber(QPoint) returns the correct screen
@ -131,25 +139,28 @@ void tst_QDesktopWidget::screenNumberForQPoint()
    screen = desktopWidget->screenNumber(allScreens.bottomRight() + QPoint(1, 1));
    QVERIFY(screen >= 0 && screen < desktopWidget->numScreens());
 }
+#endif

 void tst_QDesktopWidget::screenGeometry()
 {
    QDesktopWidget *desktopWidget = QApplication::desktop();
    QTest::ignoreMessage(QtWarningMsg, "QDesktopWidget::screenGeometry(): Attempt "
                                       "to get the screen geometry of a null widget");
-    QRect r = desktopWidget->screenGeometry((QWidget *)0);
+    QRect r = desktopWidget->screenGeometry(nullptr);
    QVERIFY(r.isNull());
    QWidget widget;
    widget.show();
    QVERIFY(QTest::qWaitForWindowExposed(&widget));
    r = desktopWidget->screenGeometry(&widget);

+#if QT_DEPRECATED_SINCE(5, 11)
    QRect total;
    QRect available;
    for (int i = 0; i < desktopWidget->screenCount(); ++i) {
        total = desktopWidget->screenGeometry(i);
        available = desktopWidget->availableGeometry(i);
    }
+#endif
 }

 void tst_QDesktopWidget::topLevels()
--- a/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
+++ b/tests/auto/widgets/kernel/qwidget/tst_qwidget.cpp
@ -5383,7 +5383,7 @@ void tst_QWidget::moveChild()
    parent.setStyle(style.data());
    ColorWidget child(&parent, Qt::Widget, Qt::blue);

-    parent.setGeometry(QRect(QPoint(QApplication::desktop()->availableGeometry(&parent).topLeft()) + QPoint(50, 50),
+    parent.setGeometry(QRect(parent.screen()->availableGeometry().topLeft() + QPoint(50, 50),
                             QSize(200, 200)));
    child.setGeometry(25, 25, 50, 50);
 #ifndef QT_NO_CURSOR // Try to make sure the cursor is not in a taskbar area to prevent tooltips or window highlighting
@ -5430,8 +5430,7 @@ void tst_QWidget::showAndMoveChild()
    const QScopedPointer<QStyle> style(QStyleFactory::create(QLatin1String("Windows")));
    parent.setStyle(style.data());

-    QDesktopWidget desktop;
-    QRect desktopDimensions = desktop.availableGeometry(&parent);
+    QRect desktopDimensions = parent.screen()->availableGeometry();
    desktopDimensions = desktopDimensions.adjusted(64, 64, -64, -64);

 #ifndef QT_NO_CURSOR // Try to make sure the cursor is not in a taskbar area to prevent tooltips or window highlighting
@ -7708,7 +7707,7 @@ void tst_QWidget::repaintWhenChildDeleted()
 #endif
    ColorWidget w(nullptr, Qt::FramelessWindowHint, Qt::red);
    w.setWindowTitle(QLatin1String(QTest::currentTestFunction()));
-    QPoint startPoint = QApplication::desktop()->availableGeometry(&w).topLeft();
+    QPoint startPoint = w.screen()->availableGeometry().topLeft();
    startPoint.rx() += 50;
    startPoint.ry() += 50;
    w.setGeometry(QRect(startPoint, QSize(100, 100)));
@ -7733,7 +7732,7 @@ void tst_QWidget::hideOpaqueChildWhileHidden()
 {
    ColorWidget w(nullptr, Qt::FramelessWindowHint, Qt::red);
    w.setWindowTitle(QLatin1String(QTest::currentTestFunction()));
-    QPoint startPoint = QApplication::desktop()->availableGeometry(&w).topLeft();
+    QPoint startPoint = w.screen()->availableGeometry().topLeft();
    startPoint.rx() += 50;
    startPoint.ry() += 50;
    w.setGeometry(QRect(startPoint, QSize(100, 100)));
@ -9601,8 +9600,7 @@ void tst_QWidget::rectOutsideCoordinatesLimit_task144779()
    palette.setColor(QPalette::Window, Qt::red);
    main.setPalette(palette);

-    QDesktopWidget desktop;
-    QRect desktopDimensions = desktop.availableGeometry(&main);
+    QRect desktopDimensions = main.screen()->availableGeometry();
    QSize mainSize(400, 400);
    mainSize = mainSize.boundedTo(desktopDimensions.size());
    main.resize(mainSize);
--- a/tests/auto/widgets/util/qcompleter/tst_qcompleter.cpp
+++ b/tests/auto/widgets/util/qcompleter/tst_qcompleter.cpp
@ -1774,7 +1774,7 @@ void tst_QCompleter::QTBUG_52028_tabAutoCompletes()
    auto le = new QLineEdit;
    w.layout()->addWidget(le);

-    const auto pos = QApplication::desktop()->availableGeometry(&w).topLeft() + QPoint(200,200);
+    const auto pos = w.screen()->availableGeometry().topLeft() + QPoint(200,200);
    w.move(pos);
    w.show();
    QApplication::setActiveWindow(&w);
@ -1815,7 +1815,7 @@ void tst_QCompleter::QTBUG_51889_activatedSentTwice()

    w.layout()->addWidget(new QLineEdit);

-    const auto pos = QApplication::desktop()->availableGeometry(&w).topLeft() + QPoint(200,200);
+    const auto pos = w.screen()->availableGeometry().topLeft() + QPoint(200,200);
    w.move(pos);
    w.show();
    QApplication::setActiveWindow(&w);
--- a/tests/auto/widgets/widgets/qcombobox/tst_qcombobox.cpp
+++ b/tests/auto/widgets/widgets/qcombobox/tst_qcombobox.cpp
@ -34,7 +34,6 @@
 #include <qpa/qplatformtheme.h>

 #include <qfontcombobox.h>
-#include <qdesktopwidget.h>
 #include <qapplication.h>
 #include <qpushbutton.h>
 #include <qdialog.h>
@ -2212,15 +2211,13 @@ void tst_QComboBox::itemListPosition()
    QFontComboBox combo(&topLevel);

    layout->addWidget(&combo);
-    //the code to get the available screen space is copied from QComboBox code
-    const int scrNumber = QApplication::desktop()->screenNumber(&combo);

    bool useFullScreenForPopupMenu = false;
    if (const QPlatformTheme *theme = QGuiApplicationPrivate::platformTheme())
        useFullScreenForPopupMenu = theme->themeHint(QPlatformTheme::UseFullScreenForPopupMenu).toBool();
    const QRect screen = useFullScreenForPopupMenu ?
-                         QApplication::screens().at(scrNumber)->geometry() :
-                         QApplication::screens().at(scrNumber)->availableGeometry();
+                         combo.screen()->geometry() :
+                         combo.screen()->availableGeometry();

    topLevel.move(screen.width() - topLevel.sizeHint().width() - 10, 0); //puts the combo to the top-right corner

@ -2440,8 +2437,7 @@ void tst_QComboBox::task248169_popupWithMinimalSize()
 #if defined QT_BUILD_INTERNAL
    QFrame *container = comboBox.findChild<QComboBoxPrivateContainer *>();
    QVERIFY(container);
-    QDesktopWidget desktop;
-    QTRY_VERIFY(desktop.screenGeometry(container).contains(container->geometry()));
+    QTRY_VERIFY(container->screen()->geometry().contains(container->geometry()));
 #endif
 }

--- a/tests/auto/widgets/widgets/qmenubar/tst_qmenubar.cpp
+++ b/tests/auto/widgets/widgets/qmenubar/tst_qmenubar.cpp
@ -34,7 +34,6 @@
 #include <qstyle.h>
 #include <qproxystyle.h>
 #include <qstylefactory.h>
-#include <qdesktopwidget.h>
 #include <qaction.h>
 #include <qstyleoption.h>
 #include <QVBoxLayout>
@ -1149,8 +1148,8 @@ void tst_QMenuBar::check_menuPosition()

    Menu menu;
    menu.setTitle("&menu");
-    QRect availRect = QApplication::desktop()->availableGeometry(&w);
-    QRect screenRect = QApplication::desktop()->screenGeometry(&w);
+    QRect availRect = w.screen()->availableGeometry();
+    QRect screenRect = w.screen()->geometry();

    while(menu.sizeHint().height() < (screenRect.height()*2/3)) {
        menu.addAction("item");
--- a/tests/manual/dialogs/printdialogpanel.cpp
+++ b/tests/manual/dialogs/printdialogpanel.cpp
@ -710,8 +710,7 @@ void PrintDialogPanel::showPreviewDialog()
    applySettings(m_printer.data());
    PrintPreviewDialog dialog(m_printer.data(), this);
 #if QT_VERSION >= 0x050000
-    const int screenNumber = QApplication::desktop()->screenNumber(this);
-    const QSize availableSize = QGuiApplication::screens().at(screenNumber)->availableSize();
+    const QSize availableSize = screen()->availableSize();
 #else
    const QSize availableSize = QApplication::desktop()->availableGeometry().size();
 #endif
--- a/tests/manual/qcursor/qcursorhighdpi/main.cpp
+++ b/tests/manual/qcursor/qcursorhighdpi/main.cpp
@ -218,7 +218,7 @@ protected:

 VerticalRuler::VerticalRuler(QWidget *parent) : QWidget(parent)
 {
-    const int screenWidth = QApplication::desktop()->screenGeometry(this).width();
+    const int screenWidth = screen()->geometry().width();
    setFixedWidth(screenWidth / 48); // 1920 pixel monitor ->40
 }

@ -356,15 +356,12 @@ int main(int argc, char *argv[])
    QApplication app(argc, argv);

    MainWindowPtrList windows;
-
-    QDesktopWidget *desktopWidget = app.desktop();
-
    const int lastScreen = arguments.contains("-p")
        ? 0  // Primary screen only
-        : desktopWidget->screenCount() - 1; // All screens
+        : QGuiApplication::screens().size() - 1; // All screens
    for (int s = lastScreen; s >= 0; --s) {
-        MainWindowPtr window(new MainWindow(desktopWidget->screen(s)));
-        const QPoint pos = desktopWidget->screenGeometry(s).center() - QPoint(200, 100);
+        MainWindowPtr window(new MainWindow());
+        const QPoint pos = QGuiApplication::screens().at(s)->geometry().center() - QPoint(200, 100);
        window->move(pos);
        windows.append(window);
        window->show();
--- a/tests/manual/qdesktopwidget/main.cpp
+++ b/tests/manual/qdesktopwidget/main.cpp
@ -34,6 +34,7 @@

 class DesktopView : public QGraphicsView
 {
+#if QT_DEPRECATED_SINCE(5, 11)
    Q_OBJECT
 public:
    DesktopView()
@ -195,6 +196,7 @@ private:
    QGraphicsScene *scene;
    QGraphicsRectItem *that;
    QPoint thatRoot;
+#endif
 };

 #include "main.moc"
--- a/tests/manual/qscreen/main.cpp
+++ b/tests/manual/qscreen/main.cpp
@ -61,8 +61,10 @@ public:
                QLatin1String("Left-click to test QGuiApplication::topLevelAt(click pos)\nRight-click to ungrab\n") :
                QLatin1String("Left-click to grab mouse\n");
        if (!m_cursorPos.isNull()) {
+            const auto screen = QGuiApplication::screenAt(m_cursorPos);
+            const auto screenNum = screen ? QGuiApplication::screens().indexOf(screen) : 0;
            txt += QString(QLatin1String("Current mouse position: %1, %2 on screen %3\n"))
-                    .arg(m_cursorPos.x()).arg(m_cursorPos.y()).arg(QApplication::desktop()->screenNumber(m_cursorPos));
+                    .arg(m_cursorPos.x()).arg(m_cursorPos.y()).arg(screenNum);
            if (QGuiApplication::mouseButtons() & Qt::LeftButton) {
                QWindow *win = QGuiApplication::topLevelAt(m_cursorPos);
                txt += QString(QLatin1String("Top-level window found? %1\n"))
@ -234,6 +236,7 @@ void screenAdded(QScreen* screen)
    QList<QScreen *> screens = QGuiApplication::screens();
    int screenNumber = screens.indexOf(screen);
    Q_ASSERT(screenNumber >= 0);
+    // ### Qt 6: Find a replacement for QDesktopWidget::screen()
    w->setParent(qApp->desktop()->screen(screenNumber));

    w->show();