diff --git a/composite.cpp b/composite.cpp
index a5341460b..5551210b8 100644
--- a/composite.cpp
+++ b/composite.cpp
@@ -1,1215 +1,1215 @@
 /********************************************************************
  KWin - the KDE window manager
  This file is part of the KDE project.
 
 Copyright (C) 2006 Lubos Lunak <l.lunak@kde.org>
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
 
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *********************************************************************/
 #include "composite.h"
 
 #include "dbusinterface.h"
 #include "utils.h"
 #include <QTextStream>
 #include "workspace.h"
 #include "client.h"
 #include "unmanaged.h"
 #include "deleted.h"
 #include "effects.h"
 #include "overlaywindow.h"
 #include "scene.h"
 #include "screens.h"
 #include "shadow.h"
 #include "useractions.h"
 #include "xcbutils.h"
 #include "platform.h"
 #include "shell_client.h"
 #include "wayland_server.h"
 #include "decorations/decoratedclient.h"
 
 #include <kwingltexture.h>
 
 #include <KWayland/Server/surface_interface.h>
 
 #include <stdio.h>
 
 #include <QtConcurrentRun>
 #include <QFutureWatcher>
 #include <QMenu>
 #include <QTimerEvent>
 #include <QDateTime>
 #include <QOpenGLContext>
 #include <QQuickWindow>
 #include <KGlobalAccel>
 #include <KLocalizedString>
 #include <KPluginLoader>
 #include <KPluginMetaData>
 #include <KNotification>
 #include <KSelectionWatcher>
 
 #include <xcb/composite.h>
 #include <xcb/damage.h>
 
 Q_DECLARE_METATYPE(KWin::Compositor::SuspendReason)
 
 namespace KWin
 {
 
 extern int currentRefreshRate();
 
 CompositorSelectionOwner::CompositorSelectionOwner(const char *selection) : KSelectionOwner(selection, connection(), rootWindow()), owning(false)
 {
     connect (this, SIGNAL(lostOwnership()), SLOT(looseOwnership()));
 }
 
 void CompositorSelectionOwner::looseOwnership()
 {
     owning = false;
 }
 
 KWIN_SINGLETON_FACTORY_VARIABLE(Compositor, s_compositor)
 
 static inline qint64 milliToNano(int milli) { return qint64(milli) * 1000 * 1000; }
 static inline qint64 nanoToMilli(int nano) { return nano / (1000*1000); }
 
 Compositor::Compositor(QObject* workspace)
     : QObject(workspace)
     , m_suspended(options->isUseCompositing() ? NoReasonSuspend : UserSuspend)
     , cm_selection(NULL)
     , vBlankInterval(0)
     , fpsInterval(0)
     , m_xrrRefreshRate(0)
     , m_finishing(false)
     , m_starting(false)
     , m_timeSinceLastVBlank(0)
     , m_scene(NULL)
     , m_bufferSwapPending(false)
     , m_composeAtSwapCompletion(false)
 {
     qRegisterMetaType<Compositor::SuspendReason>("Compositor::SuspendReason");
     connect(&compositeResetTimer, SIGNAL(timeout()), SLOT(restart()));
     connect(options, &Options::configChanged, this, &Compositor::slotConfigChanged);
     compositeResetTimer.setSingleShot(true);
     nextPaintReference.invalidate(); // Initialize the timer
 
     // 2 sec which should be enough to restart the compositor
     static const int compositorLostMessageDelay = 2000;
 
     m_releaseSelectionTimer.setSingleShot(true);
     m_releaseSelectionTimer.setInterval(compositorLostMessageDelay);
     connect(&m_releaseSelectionTimer, SIGNAL(timeout()), SLOT(releaseCompositorSelection()));
 
     m_unusedSupportPropertyTimer.setInterval(compositorLostMessageDelay);
     m_unusedSupportPropertyTimer.setSingleShot(true);
     connect(&m_unusedSupportPropertyTimer, SIGNAL(timeout()), SLOT(deleteUnusedSupportProperties()));
 
     // delay the call to setup by one event cycle
     // The ctor of this class is invoked from the Workspace ctor, that means before
     // Workspace is completely constructed, so calling Workspace::self() would result
     // in undefined behavior. This is fixed by using a delayed invocation.
     if (kwinApp()->platform()->isReady()) {
         QMetaObject::invokeMethod(this, "setup", Qt::QueuedConnection);
     }
     connect(kwinApp()->platform(), &Platform::readyChanged, this,
         [this] (bool ready) {
             if (ready) {
                 setup();
             } else {
                 finish();
             }
         }, Qt::QueuedConnection
     );
     connect(kwinApp(), &Application::x11ConnectionAboutToBeDestroyed, this,
         [this] {
             delete cm_selection;
             cm_selection = nullptr;
         }
     );
 
     if (qEnvironmentVariableIsSet("KWIN_MAX_FRAMES_TESTED"))
        m_framesToTestForSafety = qEnvironmentVariableIntValue("KWIN_MAX_FRAMES_TESTED");
 
     // register DBus
     new CompositorDBusInterface(this);
 }
 
 Compositor::~Compositor()
 {
     emit aboutToDestroy();
     finish();
     deleteUnusedSupportProperties();
     delete cm_selection;
     s_compositor = NULL;
 }
 
 
 void Compositor::setup()
 {
     if (kwinApp()->isTerminating()) {
         // don't setup while KWin is terminating. An event to restart might be lingering in the event queue due to graphics reset
         return;
     }
     if (hasScene())
         return;
     if (m_suspended) {
         QStringList reasons;
         if (m_suspended & UserSuspend) {
             reasons << QStringLiteral("Disabled by User");
         }
         if (m_suspended & BlockRuleSuspend) {
             reasons << QStringLiteral("Disabled by Window");
         }
         if (m_suspended & ScriptSuspend) {
             reasons << QStringLiteral("Disabled by Script");
         }
         qCDebug(KWIN_CORE) << "Compositing is suspended, reason:" << reasons;
         return;
     } else if (!kwinApp()->platform()->compositingPossible()) {
         qCCritical(KWIN_CORE) << "Compositing is not possible";
         return;
     }
     m_starting = true;
 
     if (!options->isCompositingInitialized()) {
         options->reloadCompositingSettings(true);
     }
     slotCompositingOptionsInitialized();
 }
 
 extern int screen_number; // main.cpp
 extern bool is_multihead;
 
 void Compositor::slotCompositingOptionsInitialized()
 {
     setupX11Support();
 
     // There might still be a deleted around, needs to be cleared before creating the scene (BUG 333275)
     if (Workspace::self()) {
         while (!Workspace::self()->deletedList().isEmpty()) {
             Workspace::self()->deletedList().first()->discard();
         }
     }
 
     auto supportedCompositors = kwinApp()->platform()->supportedCompositors();
     const auto userConfigIt = std::find(supportedCompositors.begin(), supportedCompositors.end(), options->compositingMode());
     if (userConfigIt != supportedCompositors.end()) {
         supportedCompositors.erase(userConfigIt);
         supportedCompositors.prepend(options->compositingMode());
     } else {
         qCWarning(KWIN_CORE) << "Configured compositor not supported by Platform. Falling back to defaults";
     }
 
     const auto availablePlugins = KPluginLoader::findPlugins(QStringLiteral("org.kde.kwin.scenes"));
 
     for (auto type : qAsConst(supportedCompositors)) {
         const auto pluginIt = std::find_if(availablePlugins.begin(), availablePlugins.end(),
             [type] (const auto &plugin) {
                 const auto &metaData = plugin.rawData();
                 auto it = metaData.find(QStringLiteral("CompositingType"));
                 if (it != metaData.end()) {
                     if ((*it).toInt() == int{type}) {
                         return true;
                     }
                 }
                 return false;
             });
         if (pluginIt != availablePlugins.end()) {
             std::unique_ptr<SceneFactory> factory{qobject_cast<SceneFactory*>(pluginIt->instantiate())};
             if (factory) {
                 m_scene = factory->create(this);
                 if (m_scene) {
                     if (!m_scene->initFailed()) {
                         qCDebug(KWIN_CORE) << "Instantiated compositing plugin:" << pluginIt->name();
                         break;
                     } else {
                         delete m_scene;
                         m_scene = nullptr;
                     }
                 }
             }
         }
     }
 
     if (m_scene == NULL || m_scene->initFailed()) {
         qCCritical(KWIN_CORE) << "Failed to initialize compositing, compositing disabled";
         delete m_scene;
         m_scene = NULL;
         m_starting = false;
         if (cm_selection) {
             cm_selection->owning = false;
             cm_selection->release();
         }
         if (!supportedCompositors.contains(NoCompositing)) {
             qCCritical(KWIN_CORE) << "The used windowing system requires compositing";
             qCCritical(KWIN_CORE) << "We are going to quit KWin now as it is broken";
             qApp->quit();
         }
         return;
     }
 
     if (!Workspace::self() && m_scene && m_scene->compositingType() == QPainterCompositing) {
         // Force Software QtQuick on first startup with QPainter
         QQuickWindow::setSceneGraphBackend(QSGRendererInterface::Software);
     }
 
     connect(m_scene, &Scene::resetCompositing, this, &Compositor::restart);
     emit sceneCreated();
 
     if (Workspace::self()) {
         startupWithWorkspace();
     } else {
         connect(kwinApp(), &Application::workspaceCreated, this, &Compositor::startupWithWorkspace);
     }
 }
 
 void Compositor::claimCompositorSelection()
 {
     if (!cm_selection) {
         char selection_name[ 100 ];
         sprintf(selection_name, "_NET_WM_CM_S%d", Application::x11ScreenNumber());
         cm_selection = new CompositorSelectionOwner(selection_name);
         connect(cm_selection, SIGNAL(lostOwnership()), SLOT(finish()));
     }
 
     if (!cm_selection) // no X11 yet
         return;
 
     if (!cm_selection->owning) {
         cm_selection->claim(true);   // force claiming
         cm_selection->owning = true;
     }
 }
 
 void Compositor::setupX11Support()
 {
     auto c = kwinApp()->x11Connection();
     if (!c) {
         delete cm_selection;
         cm_selection = nullptr;
         return;
     }
     claimCompositorSelection();
     xcb_composite_redirect_subwindows(c, kwinApp()->x11RootWindow(), XCB_COMPOSITE_REDIRECT_MANUAL);
 }
 
 void Compositor::startupWithWorkspace()
 {
     if (!m_starting) {
         return;
     }
     connect(kwinApp(), &Application::x11ConnectionChanged, this, &Compositor::setupX11Support, Qt::UniqueConnection);
     Workspace::self()->markXStackingOrderAsDirty();
     Q_ASSERT(m_scene);
     connect(workspace(), &Workspace::destroyed, this, [this] { compositeTimer.stop(); });
     setupX11Support();
     m_xrrRefreshRate = KWin::currentRefreshRate();
     fpsInterval = options->maxFpsInterval();
     if (m_scene->syncsToVBlank()) {  // if we do vsync, set the fps to the next multiple of the vblank rate
         vBlankInterval = milliToNano(1000) / m_xrrRefreshRate;
         fpsInterval = qMax((fpsInterval / vBlankInterval) * vBlankInterval, vBlankInterval);
     } else
         vBlankInterval = milliToNano(1); // no sync - DO NOT set "0", would cause div-by-zero segfaults.
     m_timeSinceLastVBlank = fpsInterval - (options->vBlankTime() + 1); // means "start now" - we don't have even a slight idea when the first vsync will occur
     scheduleRepaint();
     kwinApp()->platform()->createEffectsHandler(this, m_scene);   // sets also the 'effects' pointer
     connect(Workspace::self(), &Workspace::deletedRemoved, m_scene, &Scene::windowDeleted);
     connect(effects, SIGNAL(screenGeometryChanged(QSize)), SLOT(addRepaintFull()));
     addRepaintFull();
     foreach (Client * c, Workspace::self()->clientList()) {
         c->setupCompositing();
         c->getShadow();
     }
     foreach (Client * c,  Workspace::self()->desktopList())
         c->setupCompositing();
     foreach (Unmanaged * c, Workspace::self()->unmanagedList()) {
         c->setupCompositing();
         c->getShadow();
     }
     if (auto w = waylandServer()) {
         const auto clients = w->clients();
         for (auto c : clients) {
             c->setupCompositing();
             c->getShadow();
         }
         const auto internalClients = w->internalClients();
         for (auto c : internalClients) {
             c->setupCompositing();
             c->getShadow();
         }
     }
 
     emit compositingToggled(true);
 
     m_starting = false;
     if (m_releaseSelectionTimer.isActive()) {
         m_releaseSelectionTimer.stop();
     }
 
     // render at least once
     performCompositing();
 }
 
 void Compositor::scheduleRepaint()
 {
     if (!compositeTimer.isActive())
         setCompositeTimer();
 }
 
 void Compositor::finish()
 {
     if (!hasScene())
         return;
     m_finishing = true;
     m_releaseSelectionTimer.start();
 
     // Some effects might need access to effect windows when they are about to
     // be destroyed, for example to unreference deleted windows, so we have to
     // make sure that effect windows outlive effects.
     delete effects;
     effects = nullptr;
 
     if (Workspace::self()) {
         foreach (Client * c, Workspace::self()->clientList())
             m_scene->windowClosed(c, NULL);
         foreach (Client * c, Workspace::self()->desktopList())
             m_scene->windowClosed(c, NULL);
         foreach (Unmanaged * c, Workspace::self()->unmanagedList())
             m_scene->windowClosed(c, NULL);
         foreach (Deleted * c, Workspace::self()->deletedList())
             m_scene->windowDeleted(c);
         foreach (Client * c, Workspace::self()->clientList())
         c->finishCompositing();
         foreach (Client * c, Workspace::self()->desktopList())
         c->finishCompositing();
         foreach (Unmanaged * c, Workspace::self()->unmanagedList())
         c->finishCompositing();
         foreach (Deleted * c, Workspace::self()->deletedList())
         c->finishCompositing();
         if (auto c = kwinApp()->x11Connection()) {
             xcb_composite_unredirect_subwindows(c, kwinApp()->x11RootWindow(), XCB_COMPOSITE_REDIRECT_MANUAL);
         }
     }
     if (waylandServer()) {
         foreach (ShellClient *c, waylandServer()->clients()) {
             m_scene->windowClosed(c, nullptr);
         }
         foreach (ShellClient *c, waylandServer()->internalClients()) {
             m_scene->windowClosed(c, nullptr);
         }
         foreach (ShellClient *c, waylandServer()->clients()) {
             c->finishCompositing();
         }
         foreach (ShellClient *c, waylandServer()->internalClients()) {
             c->finishCompositing();
         }
     }
     delete m_scene;
     m_scene = NULL;
     compositeTimer.stop();
     repaints_region = QRegion();
     if (Workspace::self()) {
         for (ClientList::ConstIterator it = Workspace::self()->clientList().constBegin();
                 it != Workspace::self()->clientList().constEnd();
                 ++it) {
             // forward all opacity values to the frame in case there'll be other CM running
             if ((*it)->opacity() != 1.0) {
                 NETWinInfo i(connection(), (*it)->frameId(), rootWindow(), 0, 0);
                 i.setOpacity(static_cast< unsigned long >((*it)->opacity() * 0xffffffff));
             }
         }
         // discard all Deleted windows (#152914)
         while (!Workspace::self()->deletedList().isEmpty())
             Workspace::self()->deletedList().first()->discard();
     }
     m_finishing = false;
     emit compositingToggled(false);
 }
 
 void Compositor::releaseCompositorSelection()
 {
     if (hasScene() && !m_finishing) {
         // compositor is up and running again, no need to release the selection
         return;
     }
     if (m_starting) {
         // currently still starting the compositor, it might fail, so restart the timer to test again
         m_releaseSelectionTimer.start();
         return;
     }
 
     if (m_finishing) {
         // still shutting down, a restart might follow, so restart the timer to test again
         m_releaseSelectionTimer.start();
         return;
     }
     qCDebug(KWIN_CORE) << "Releasing compositor selection";
     if (cm_selection) {
         cm_selection->owning = false;
         cm_selection->release();
     }
 }
 
 void Compositor::keepSupportProperty(xcb_atom_t atom)
 {
     m_unusedSupportProperties.removeAll(atom);
 }
 
 void Compositor::removeSupportProperty(xcb_atom_t atom)
 {
     m_unusedSupportProperties << atom;
     m_unusedSupportPropertyTimer.start();
 }
 
 void Compositor::deleteUnusedSupportProperties()
 {
     if (m_starting) {
         // currently still starting the compositor
         m_unusedSupportPropertyTimer.start();
         return;
     }
     if (m_finishing) {
         // still shutting down, a restart might follow
         m_unusedSupportPropertyTimer.start();
         return;
     }
     if (const auto c = kwinApp()->x11Connection()) {
         foreach (const xcb_atom_t &atom, m_unusedSupportProperties) {
             // remove property from root window
             xcb_delete_property(c, kwinApp()->x11RootWindow(), atom);
         }
     }
 }
 
 void Compositor::slotConfigChanged()
 {
     if (!m_suspended) {
         setup();
         if (effects)   // setupCompositing() may fail
             effects->reconfigure();
         addRepaintFull();
     } else
         finish();
 }
 
 void Compositor::slotReinitialize()
 {
     // Reparse config. Config options will be reloaded by setup()
     kwinApp()->config()->reparseConfiguration();
 
     // Restart compositing
     finish();
     // resume compositing if suspended
     m_suspended = NoReasonSuspend;
     options->setCompositingInitialized(false);
     setup();
 
     if (effects) { // setup() may fail
         effects->reconfigure();
     }
 }
 
 // for the shortcut
 void Compositor::slotToggleCompositing()
 {
     if (kwinApp()->platform()->requiresCompositing()) {
         // we are not allowed to turn on/off compositing
         return;
     }
     if (m_suspended) { // direct user call; clear all bits
         resume(AllReasonSuspend);
     } else { // but only set the user one (sufficient to suspend)
         suspend(UserSuspend);
     }
 }
 
 void Compositor::updateCompositeBlocking()
 {
     updateCompositeBlocking(NULL);
 }
 
 void Compositor::updateCompositeBlocking(Client *c)
 {
     if (kwinApp()->platform()->requiresCompositing()) {
         return;
     }
     if (c) { // if c == 0 we just check if we can resume
         if (c->isBlockingCompositing()) {
             if (!(m_suspended & BlockRuleSuspend)) // do NOT attempt to call suspend(true); from within the eventchain!
                 QMetaObject::invokeMethod(this, "suspend", Qt::QueuedConnection, Q_ARG(Compositor::SuspendReason, BlockRuleSuspend));
         }
     }
     else if (m_suspended & BlockRuleSuspend) {  // lost a client and we're blocked - can we resume?
         bool resume = true;
         for (ClientList::ConstIterator it = Workspace::self()->clientList().constBegin(); it != Workspace::self()->clientList().constEnd(); ++it) {
             if ((*it)->isBlockingCompositing()) {
                 resume = false;
                 break;
             }
         }
         if (resume) { // do NOT attempt to call suspend(false); from within the eventchain!
             QMetaObject::invokeMethod(this, "resume", Qt::QueuedConnection, Q_ARG(Compositor::SuspendReason, BlockRuleSuspend));
         }
     }
 }
 
 void Compositor::suspend(Compositor::SuspendReason reason)
 {
     if (kwinApp()->platform()->requiresCompositing()) {
         return;
     }
     Q_ASSERT(reason != NoReasonSuspend);
     m_suspended |= reason;
     if (reason & KWin::Compositor::ScriptSuspend) {
         // when disabled show a shortcut how the user can get back compositing
         const auto shortcuts = KGlobalAccel::self()->shortcut(workspace()->findChild<QAction*>(QStringLiteral("Suspend Compositing")));
         if (!shortcuts.isEmpty()) {
             // display notification only if there is the shortcut
             const QString message = i18n("Desktop effects have been suspended by another application.<br/>"
                                          "You can resume using the '%1' shortcut.", shortcuts.first().toString(QKeySequence::NativeText));
             KNotification::event(QStringLiteral("compositingsuspendeddbus"), message);
         }
     }
     finish();
 }
 
 void Compositor::resume(Compositor::SuspendReason reason)
 {
     Q_ASSERT(reason != NoReasonSuspend);
     m_suspended &= ~reason;
     setup(); // signal "toggled" is eventually emitted from within setup
 }
 
 void Compositor::restart()
 {
     if (hasScene()) {
         finish();
         QTimer::singleShot(0, this, SLOT(setup()));
     }
 }
 
 void Compositor::addRepaint(int x, int y, int w, int h)
 {
     if (!hasScene())
         return;
     repaints_region += QRegion(x, y, w, h);
     scheduleRepaint();
 }
 
 void Compositor::addRepaint(const QRect& r)
 {
     if (!hasScene())
         return;
     repaints_region += r;
     scheduleRepaint();
 }
 
 void Compositor::addRepaint(const QRegion& r)
 {
     if (!hasScene())
         return;
     repaints_region += r;
     scheduleRepaint();
 }
 
 void Compositor::addRepaintFull()
 {
     if (!hasScene())
         return;
     const QSize &s = screens()->size();
     repaints_region = QRegion(0, 0, s.width(), s.height());
     scheduleRepaint();
 }
 
 void Compositor::timerEvent(QTimerEvent *te)
 {
     if (te->timerId() == compositeTimer.timerId()) {
         performCompositing();
     } else
         QObject::timerEvent(te);
 }
 
 void Compositor::aboutToSwapBuffers()
 {
     assert(!m_bufferSwapPending);
 
     m_bufferSwapPending = true;
 }
 
 void Compositor::bufferSwapComplete()
 {
     assert(m_bufferSwapPending);
     m_bufferSwapPending = false;
 
     if (m_composeAtSwapCompletion) {
         m_composeAtSwapCompletion = false;
         performCompositing();
     }
 }
 
 void Compositor::performCompositing()
 {
     if (m_scene->usesOverlayWindow() && !isOverlayWindowVisible())
         return; // nothing is visible anyway
 
     // If a buffer swap is still pending, we return to the event loop and
     // continue processing events until the swap has completed.
     if (m_bufferSwapPending) {
         m_composeAtSwapCompletion = true;
         compositeTimer.stop();
         return;
     }
 
     // If outputs are disabled, we return to the event loop and
     // continue processing events until the outputs are enabled again
     if (!kwinApp()->platform()->areOutputsEnabled()) {
         compositeTimer.stop();
         return;
     }
 
     // Create a list of all windows in the stacking order
     ToplevelList windows = Workspace::self()->xStackingOrder();
     ToplevelList damaged;
 
     // Reset the damage state of each window and fetch the damage region
     // without waiting for a reply
     foreach (Toplevel *win, windows) {
         if (win->resetAndFetchDamage())
             damaged << win;
     }
 
     if (damaged.count() > 0) {
         m_scene->triggerFence();
         if (auto c = kwinApp()->x11Connection()) {
             xcb_flush(c);
         }
     }
 
     // Move elevated windows to the top of the stacking order
     foreach (EffectWindow *c, static_cast<EffectsHandlerImpl *>(effects)->elevatedWindows()) {
         Toplevel* t = static_cast< EffectWindowImpl* >(c)->window();
         windows.removeAll(t);
         windows.append(t);
     }
 
     // Get the replies
     foreach (Toplevel *win, damaged) {
         // Discard the cached lanczos texture
         if (win->effectWindow()) {
             const QVariant texture = win->effectWindow()->data(LanczosCacheRole);
             if (texture.isValid()) {
                 delete static_cast<GLTexture *>(texture.value<void*>());
                 win->effectWindow()->setData(LanczosCacheRole, QVariant());
             }
         }
 
         win->getDamageRegionReply();
     }
 
     if (repaints_region.isEmpty() && !windowRepaintsPending()) {
         m_scene->idle();
         m_timeSinceLastVBlank = fpsInterval - (options->vBlankTime() + 1); // means "start now"
         m_timeSinceStart += m_timeSinceLastVBlank;
         // Note: It would seem here we should undo suspended unredirect, but when scenes need
         // it for some reason, e.g. transformations or translucency, the next pass that does not
         // need this anymore and paints normally will also reset the suspended unredirect.
         // Otherwise the window would not be painted normally anyway.
         compositeTimer.stop();
         return;
     }
 
     // skip windows that are not yet ready for being painted and if screen is locked skip windows that are
     // neither lockscreen nor inputmethod windows
     // TODO ?
     // this cannot be used so carelessly - needs protections against broken clients, the window
     // should not get focus before it's displayed, handle unredirected windows properly and so on.
     foreach (Toplevel *t, windows) {
         if (!t->readyForPainting()) {
             windows.removeAll(t);
         }
         if (waylandServer() && waylandServer()->isScreenLocked()) {
             if(!t->isLockScreen() && !t->isInputMethod()) {
                 windows.removeAll(t);
             }
         }
     }
 
     QRegion repaints = repaints_region;
     // clear all repaints, so that post-pass can add repaints for the next repaint
     repaints_region = QRegion();
 
     if (m_framesToTestForSafety > 0 && (m_scene->compositingType() & OpenGLCompositing)) {
         kwinApp()->platform()->createOpenGLSafePoint(Platform::OpenGLSafePoint::PreFrame);
     }
     m_timeSinceLastVBlank = m_scene->paint(repaints, windows);
     if (m_framesToTestForSafety > 0) {
         if (m_scene->compositingType() & OpenGLCompositing) {
             kwinApp()->platform()->createOpenGLSafePoint(Platform::OpenGLSafePoint::PostFrame);
         }
         m_framesToTestForSafety--;
         if (m_framesToTestForSafety == 0 && (m_scene->compositingType() & OpenGLCompositing)) {
             kwinApp()->platform()->createOpenGLSafePoint(Platform::OpenGLSafePoint::PostLastGuardedFrame);
         }
     }
     m_timeSinceStart += m_timeSinceLastVBlank;
 
     if (waylandServer()) {
-        for (Toplevel *win : qAsConst(damaged)) {
+        for (Toplevel *win : qAsConst(windows)) {
             if (auto surface = win->surface()) {
                 surface->frameRendered(m_timeSinceStart);
             }
         }
     }
 
     compositeTimer.stop(); // stop here to ensure *we* cause the next repaint schedule - not some effect through m_scene->paint()
 
     // Trigger at least one more pass even if there would be nothing to paint, so that scene->idle()
     // is called the next time. If there would be nothing pending, it will not restart the timer and
     // scheduleRepaint() would restart it again somewhen later, called from functions that
     // would again add something pending.
     if (m_bufferSwapPending && m_scene->syncsToVBlank()) {
         m_composeAtSwapCompletion = true;
     } else {
         scheduleRepaint();
     }
 }
 
 template <class T>
 static bool repaintsPending(const QList<T*> &windows)
 {
     return std::any_of(windows.begin(), windows.end(), [] (T *t) { return !t->repaints().isEmpty(); });
 }
 
 bool Compositor::windowRepaintsPending() const
 {
     if (repaintsPending(Workspace::self()->clientList())) {
         return true;
     }
     if (repaintsPending(Workspace::self()->desktopList())) {
         return true;
     }
     if (repaintsPending(Workspace::self()->unmanagedList())) {
         return true;
     }
     if (repaintsPending(Workspace::self()->deletedList())) {
         return true;
     }
     if (auto w = waylandServer()) {
         const auto &clients = w->clients();
         auto test = [] (ShellClient *c) {
             return c->readyForPainting() && !c->repaints().isEmpty();
         };
         if (std::any_of(clients.begin(), clients.end(), test)) {
             return true;
         }
         const auto &internalClients = w->internalClients();
         auto internalTest = [] (ShellClient *c) {
             return c->isShown(true) && !c->repaints().isEmpty();
         };
         if (std::any_of(internalClients.begin(), internalClients.end(), internalTest)) {
             return true;
         }
     }
     return false;
 }
 
 void Compositor::setCompositeResetTimer(int msecs)
 {
     compositeResetTimer.start(msecs);
 }
 
 void Compositor::setCompositeTimer()
 {
     if (!hasScene())  // should not really happen, but there may be e.g. some damage events still pending
         return;
     if (m_starting || !Workspace::self()) {
         return;
     }
 
     // Don't start the timer if we're waiting for a swap event
     if (m_bufferSwapPending && m_composeAtSwapCompletion)
         return;
 
     // Don't start the timer if all outputs are disabled
     if (!kwinApp()->platform()->areOutputsEnabled()) {
         return;
     }
 
     uint waitTime = 1;
 
     if (m_scene->blocksForRetrace()) {
 
         // TODO: make vBlankTime dynamic?!
         // It's required because glXWaitVideoSync will *likely* block a full frame if one enters
         // a retrace pass which can last a variable amount of time, depending on the actual screen
         // Now, my ooold 19" CRT can do such retrace so that 2ms are entirely sufficient,
         // while another ooold 15" TFT requires about 6ms
 
         qint64 padding = m_timeSinceLastVBlank;
         if (padding > fpsInterval) {
             // we're at low repaints or spent more time in painting than the user wanted to wait for that frame
             padding = vBlankInterval - (padding%vBlankInterval); // -> align to next vblank
         } else {  // -> align to the next maxFps tick
             padding = ((vBlankInterval - padding%vBlankInterval) + (fpsInterval/vBlankInterval-1)*vBlankInterval);
             //               "remaining time of the first vsync" + "time for the other vsyncs of the frame"
         }
 
         if (padding < options->vBlankTime()) { // we'll likely miss this frame
             waitTime = nanoToMilli(padding + vBlankInterval - options->vBlankTime()); // so we add one
         } else {
             waitTime = nanoToMilli(padding - options->vBlankTime());
         }
     }
     else { // w/o blocking vsync we just jump to the next demanded tick
         if (fpsInterval > m_timeSinceLastVBlank) {
             waitTime = nanoToMilli(fpsInterval - m_timeSinceLastVBlank);
             if (!waitTime) {
                 waitTime = 1; // will ensure we don't block out the eventloop - the system's just not faster ...
             }
         }/* else if (m_scene->syncsToVBlank() && m_timeSinceLastVBlank - fpsInterval < (vBlankInterval<<1)) {
             // NOTICE - "for later" ------------------------------------------------------------------
             // It can happen that we push two frames within one refresh cycle.
             // Swapping will then block even with triple buffering when the GPU does not discard but
             // queues frames
             // now here's the mean part: if we take that as "OMG, we're late - next frame ASAP",
             // there'll immediately be 2 frames in the pipe, swapping will block, we think we're
             // late ... ewww
             // so instead we pad to the clock again and add 2ms safety to ensure the pipe is really
             // free
             // NOTICE: obviously m_timeSinceLastVBlank can be too big because we're too slow as well
             // So if this code was enabled, we'd needlessly half the framerate once more (15 instead of 30)
             waitTime = nanoToMilli(vBlankInterval - (m_timeSinceLastVBlank - fpsInterval)%vBlankInterval) + 2;
         }*/ else {
             waitTime = 1; // ... "0" would be sufficient, but the compositor isn't the WMs only task
         }
     }
     compositeTimer.start(qMin(waitTime, 250u), this); // force 4fps minimum
 }
 
 bool Compositor::isActive()
 {
     return !m_finishing && hasScene();
 }
 
 bool Compositor::checkForOverlayWindow(WId w) const
 {
     if (!hasScene()) {
         // no scene, so it cannot be the overlay window
         return false;
     }
     if (!m_scene->overlayWindow()) {
         // no overlay window, it cannot be the overlay
         return false;
     }
     // and compare the window ID's
     return w == m_scene->overlayWindow()->window();
 }
 
 bool Compositor::isOverlayWindowVisible() const
 {
     if (!hasScene()) {
         return false;
     }
     if (!m_scene->overlayWindow()) {
         return false;
     }
     return m_scene->overlayWindow()->isVisible();
 }
 
 /*****************************************************
  * Workspace
  ****************************************************/
 
 bool Workspace::compositing() const
 {
     return m_compositor && m_compositor->hasScene();
 }
 
 //****************************************
 // Toplevel
 //****************************************
 
 bool Toplevel::setupCompositing()
 {
     if (!compositing())
         return false;
 
     if (damage_handle != XCB_NONE)
         return false;
 
     if (kwinApp()->operationMode() == Application::OperationModeX11 && !surface()) {
         damage_handle = xcb_generate_id(connection());
         xcb_damage_create(connection(), damage_handle, frameId(), XCB_DAMAGE_REPORT_LEVEL_NON_EMPTY);
     }
 
     damage_region = QRegion(0, 0, width(), height());
     effect_window = new EffectWindowImpl(this);
 
     Compositor::self()->scene()->windowAdded(this);
 
     // With unmanaged windows there is a race condition between the client painting the window
     // and us setting up damage tracking.  If the client wins we won't get a damage event even
     // though the window has been painted.  To avoid this we mark the whole window as damaged
     // and schedule a repaint immediately after creating the damage object.
     if (dynamic_cast<Unmanaged*>(this))
         addDamageFull();
 
     return true;
 }
 
 void Toplevel::finishCompositing(ReleaseReason releaseReason)
 {
     if (kwinApp()->operationMode() == Application::OperationModeX11 && damage_handle == XCB_NONE)
         return;
     if (effect_window->window() == this) { // otherwise it's already passed to Deleted, don't free data
         discardWindowPixmap();
         delete effect_window;
     }
 
     if (damage_handle != XCB_NONE &&
             releaseReason != ReleaseReason::Destroyed) {
         xcb_damage_destroy(connection(), damage_handle);
     }
 
     damage_handle = XCB_NONE;
     damage_region = QRegion();
     repaints_region = QRegion();
     effect_window = NULL;
 }
 
 void Toplevel::discardWindowPixmap()
 {
     addDamageFull();
     if (effectWindow() != NULL && effectWindow()->sceneWindow() != NULL)
         effectWindow()->sceneWindow()->pixmapDiscarded();
 }
 
 void Toplevel::damageNotifyEvent()
 {
     m_isDamaged = true;
 
     // Note: The rect is supposed to specify the damage extents,
     //       but we don't know it at this point. No one who connects
     //       to this signal uses the rect however.
     emit damaged(this, QRect());
 }
 
 bool Toplevel::compositing() const
 {
     if (!Workspace::self()) {
         return false;
     }
     return Workspace::self()->compositing();
 }
 
 void Client::damageNotifyEvent()
 {
     if (syncRequest.isPending && isResize()) {
         emit damaged(this, QRect());
         m_isDamaged = true;
         return;
     }
 
     if (!ready_for_painting) { // avoid "setReadyForPainting()" function calling overhead
         if (syncRequest.counter == XCB_NONE) {  // cannot detect complete redraw, consider done now
             setReadyForPainting();
             setupWindowManagementInterface();
         }
     }
 
     Toplevel::damageNotifyEvent();
 }
 
 bool Toplevel::resetAndFetchDamage()
 {
     if (!m_isDamaged)
         return false;
 
     if (damage_handle == XCB_NONE) {
         m_isDamaged = false;
         return true;
     }
 
     xcb_connection_t *conn = connection();
 
     // Create a new region and copy the damage region to it,
     // resetting the damaged state.
     xcb_xfixes_region_t region = xcb_generate_id(conn);
     xcb_xfixes_create_region(conn, region, 0, 0);
     xcb_damage_subtract(conn, damage_handle, 0, region);
 
     // Send a fetch-region request and destroy the region
     m_regionCookie = xcb_xfixes_fetch_region_unchecked(conn, region);
     xcb_xfixes_destroy_region(conn, region);
 
     m_isDamaged = false;
     m_damageReplyPending = true;
 
     return m_damageReplyPending;
 }
 
 void Toplevel::getDamageRegionReply()
 {
     if (!m_damageReplyPending)
         return;
 
     m_damageReplyPending = false;
 
     // Get the fetch-region reply
     xcb_xfixes_fetch_region_reply_t *reply =
             xcb_xfixes_fetch_region_reply(connection(), m_regionCookie, 0);
 
     if (!reply)
         return;
 
     // Convert the reply to a QRegion
     int count = xcb_xfixes_fetch_region_rectangles_length(reply);
     QRegion region;
 
     if (count > 1 && count < 16) {
         xcb_rectangle_t *rects = xcb_xfixes_fetch_region_rectangles(reply);
 
         QVector<QRect> qrects;
         qrects.reserve(count);
 
         for (int i = 0; i < count; i++)
             qrects << QRect(rects[i].x, rects[i].y, rects[i].width, rects[i].height);
 
         region.setRects(qrects.constData(), count);
     } else
         region += QRect(reply->extents.x, reply->extents.y,
                         reply->extents.width, reply->extents.height);
 
     damage_region += region;
     repaints_region += region;
 
     free(reply);
 }
 
 void Toplevel::addDamageFull()
 {
     if (!compositing())
         return;
 
     damage_region = rect();
     repaints_region |= rect();
 
     emit damaged(this, rect());
 }
 
 void Toplevel::resetDamage()
 {
     damage_region = QRegion();
 }
 
 void Toplevel::addRepaint(const QRect& r)
 {
     if (!compositing()) {
         return;
     }
     repaints_region += r;
     emit needsRepaint();
 }
 
 void Toplevel::addRepaint(int x, int y, int w, int h)
 {
     QRect r(x, y, w, h);
     addRepaint(r);
 }
 
 void Toplevel::addRepaint(const QRegion& r)
 {
     if (!compositing()) {
         return;
     }
     repaints_region += r;
     emit needsRepaint();
 }
 
 void Toplevel::addLayerRepaint(const QRect& r)
 {
     if (!compositing()) {
         return;
     }
     layer_repaints_region += r;
     emit needsRepaint();
 }
 
 void Toplevel::addLayerRepaint(int x, int y, int w, int h)
 {
     QRect r(x, y, w, h);
     addLayerRepaint(r);
 }
 
 void Toplevel::addLayerRepaint(const QRegion& r)
 {
     if (!compositing())
         return;
     layer_repaints_region += r;
     emit needsRepaint();
 }
 
 void Toplevel::addRepaintFull()
 {
     repaints_region = visibleRect().translated(-pos());
     emit needsRepaint();
 }
 
 void Toplevel::resetRepaints()
 {
     repaints_region = QRegion();
     layer_repaints_region = QRegion();
 }
 
 void Toplevel::addWorkspaceRepaint(int x, int y, int w, int h)
 {
     addWorkspaceRepaint(QRect(x, y, w, h));
 }
 
 void Toplevel::addWorkspaceRepaint(const QRect& r2)
 {
     if (!compositing())
         return;
     Compositor::self()->addRepaint(r2);
 }
 
 //****************************************
 // Client
 //****************************************
 
 bool Client::setupCompositing()
 {
     if (!Toplevel::setupCompositing()){
         return false;
     }
     if (isDecorated()) {
         decoratedClient()->destroyRenderer();
     }
     updateVisibility(); // for internalKeep()
     return true;
 }
 
 void Client::finishCompositing(ReleaseReason releaseReason)
 {
     Toplevel::finishCompositing(releaseReason);
     updateVisibility();
     if (!deleting) {
         if (isDecorated()) {
             decoratedClient()->destroyRenderer();
         }
     }
     // for safety in case KWin is just resizing the window
     resetHaveResizeEffect();
 }
 
 } // namespace