diff --git a/abstract_client.cpp b/abstract_client.cpp
index cbe5eb6a06..37f6d34247 100644
--- a/abstract_client.cpp
+++ b/abstract_client.cpp
@@ -34,6 +34,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "wayland_server.h"
 #include <KWayland/Server/plasmawindowmanagement_interface.h>
 
+#include <KDecoration2/Decoration>
+
 namespace KWin
 {
 
@@ -60,6 +62,7 @@ AbstractClient::AbstractClient()
 AbstractClient::~AbstractClient()
 {
     assert(m_blockGeometryUpdates == 0);
+    Q_ASSERT(m_decoration == nullptr);
 }
 
 void AbstractClient::updateMouseGrab()
@@ -1075,11 +1078,6 @@ QSize AbstractClient::sizeForClientSize(const QSize &wsize, Sizemode mode, bool
     return wsize;
 }
 
-bool AbstractClient::isDecorated() const
-{
-    return false;
-}
-
 void AbstractClient::addRepaintDuringGeometryUpdates()
 {
     const QRect deco_rect = visibleRect();
@@ -1307,4 +1305,10 @@ void AbstractClient::endMoveResize()
     updateCursor();
 }
 
+void AbstractClient::destroyDecoration()
+{
+    delete m_decoration;
+    m_decoration = nullptr;
+}
+
 }
diff --git a/abstract_client.h b/abstract_client.h
index 3e363ddec4..f39ff98c7d 100644
--- a/abstract_client.h
+++ b/abstract_client.h
@@ -35,6 +35,11 @@ class PlasmaWindowInterface;
 }
 }
 
+namespace KDecoration2
+{
+class Decoration;
+}
+
 namespace KWin
 {
 
@@ -331,7 +336,6 @@ public:
     virtual void blockActivityUpdates(bool b = true) = 0;
     QPalette palette() const;
     const Decoration::DecorationPalette *decorationPalette() const;
-    virtual bool isDecorated() const;
     virtual bool isResizable() const = 0;
     virtual bool isMovable() const = 0;
     virtual bool isMovableAcrossScreens() const = 0;
@@ -477,6 +481,17 @@ public:
     Options::MouseCommand getMouseCommand(Qt::MouseButton button, bool *handled) const;
     Options::MouseCommand getWheelCommand(Qt::Orientation orientation, bool *handled) const;
 
+    // decoration related
+    KDecoration2::Decoration *decoration() {
+        return m_decoration;
+    }
+    const KDecoration2::Decoration *decoration() const {
+        return m_decoration;
+    }
+    bool isDecorated() const {
+        return m_decoration != nullptr;
+    }
+
     // TODO: remove boolean trap
     static bool belongToSameApplication(const AbstractClient* c1, const AbstractClient* c2, bool active_hack = false);
 
@@ -777,6 +792,11 @@ protected:
         s_haveResizeEffect = false;
     }
 
+    void setDecoration(KDecoration2::Decoration *decoration) {
+        m_decoration = decoration;
+    }
+    virtual void destroyDecoration();
+
 private:
     void handlePaletteChange();
     QSharedPointer<TabBox::TabBoxClientImpl> m_tabBoxClient;
@@ -838,6 +858,8 @@ private:
         QTimer *delayedTimer = nullptr;
     } m_moveResize;
 
+    KDecoration2::Decoration *m_decoration = nullptr;
+
 
     static bool s_haveResizeEffect;
 };
diff --git a/client.cpp b/client.cpp
index e2d31ddcbd..846ed7307b 100644
--- a/client.cpp
+++ b/client.cpp
@@ -97,7 +97,6 @@ Client::Client()
     , m_client()
     , m_wrapper()
     , m_frame()
-    , m_decoration(nullptr)
     , m_activityUpdatesBlocked(false)
     , m_blockedActivityUpdatesRequireTransients(false)
     , m_moveResizeGrabWindow()
@@ -191,7 +190,6 @@ Client::~Client()
     assert(m_client == XCB_WINDOW_NONE);
     assert(m_wrapper == XCB_WINDOW_NONE);
     //assert( frameId() == None );
-    Q_ASSERT(m_decoration == nullptr);
     assert(!check_active_modal);
     for (auto it = m_connections.constBegin(); it != m_connections.constEnd(); ++it) {
         disconnect(*it);
@@ -320,8 +318,8 @@ void Client::updateInputWindow()
 
     QRegion region;
 
-    if (!noBorder() && m_decoration) {
-        const QMargins &r = m_decoration->resizeOnlyBorders();
+    if (!noBorder() && isDecorated()) {
+        const QMargins &r = decoration()->resizeOnlyBorders();
         const int left   = r.left();
         const int top    = r.top();
         const int right  = r.right();
@@ -329,9 +327,9 @@ void Client::updateInputWindow()
         if (left != 0 || top != 0 || right != 0 || bottom != 0) {
             region = QRegion(-left,
                              -top,
-                             m_decoration->size().width() + left + right,
-                             m_decoration->size().height() + top + bottom);
-            region = region.subtracted(m_decoration->rect());
+                             decoration()->size().width() + left + right,
+                             decoration()->size().height() + top + bottom);
+            region = region.subtracted(decoration()->rect());
         }
     }
 
@@ -373,7 +371,7 @@ void Client::updateInputWindow()
 void Client::updateDecoration(bool check_workspace_pos, bool force)
 {
     if (!force &&
-            ((m_decoration == NULL && noBorder()) || (m_decoration != NULL && !noBorder())))
+            ((!isDecorated() && noBorder()) || (isDecorated() && !noBorder())))
         return;
     QRect oldgeom = geometry();
     QRect oldClientGeom = oldgeom.adjusted(borderLeft(), borderTop(), -borderRight(), -borderBottom());
@@ -394,12 +392,12 @@ void Client::updateDecoration(bool check_workspace_pos, bool force)
 
 void Client::createDecoration(const QRect& oldgeom)
 {
-    m_decoration = Decoration::DecorationBridge::self()->createDecoration(this);
-    if (m_decoration) {
-        QMetaObject::invokeMethod(m_decoration, "update", Qt::QueuedConnection);
-        connect(m_decoration, &KDecoration2::Decoration::shadowChanged, this, &Toplevel::getShadow);
-        connect(m_decoration, &KDecoration2::Decoration::resizeOnlyBordersChanged, this, &Client::updateInputWindow);
-        connect(m_decoration, &KDecoration2::Decoration::bordersChanged, this,
+    KDecoration2::Decoration *decoration = Decoration::DecorationBridge::self()->createDecoration(this);
+    if (decoration) {
+        QMetaObject::invokeMethod(decoration, "update", Qt::QueuedConnection);
+        connect(decoration, &KDecoration2::Decoration::shadowChanged, this, &Toplevel::getShadow);
+        connect(decoration, &KDecoration2::Decoration::resizeOnlyBordersChanged, this, &Client::updateInputWindow);
+        connect(decoration, &KDecoration2::Decoration::bordersChanged, this,
             [this]() {
                 updateFrameExtents();
                 GeometryUpdatesBlocker blocker(this);
@@ -415,6 +413,7 @@ void Client::createDecoration(const QRect& oldgeom)
             }
         );
     }
+    setDecoration(decoration);
 
     move(calculateGravitation(false));
     plainResize(sizeForClientSize(clientSize()), ForceGeometrySet);
@@ -427,10 +426,9 @@ void Client::createDecoration(const QRect& oldgeom)
 void Client::destroyDecoration()
 {
     QRect oldgeom = geometry();
-    if (m_decoration) {
+    if (isDecorated()) {
         QPoint grav = calculateGravitation(true);
-        delete m_decoration;
-        m_decoration = nullptr;
+        AbstractClient::destroyDecoration();
         plainResize(sizeForClientSize(clientSize()), ForceGeometrySet);
         move(grav);
         if (compositing())
@@ -444,17 +442,17 @@ void Client::destroyDecoration()
 
 void Client::triggerDecorationRepaint()
 {
-    if (m_decoration) {
-        m_decoration->update();
+    if (isDecorated()) {
+        decoration()->update();
     }
 }
 
 void Client::layoutDecorationRects(QRect &left, QRect &top, QRect &right, QRect &bottom) const
 {
-    if (!m_decoration) {
+    if (!isDecorated()) {
         return;
     }
-    QRect r = m_decoration->rect();
+    QRect r = decoration()->rect();
 
     NETStrut strut = info->frameOverlap();
 
@@ -571,9 +569,7 @@ void Client::detectGtkFrameExtents()
  */
 void Client::resizeDecoration()
 {
-    if (m_decoration) {
-        m_decoration->update();
-    }
+    triggerDecorationRepaint();
     updateInputWindow();
 }
 
@@ -784,7 +780,7 @@ void Client::setShade(ShadeMode mode)
         return; // No real change in shaded state
     }
 
-    assert(m_decoration != NULL);   // noborder windows can't be shaded
+    assert(isDecorated());   // noborder windows can't be shaded
     GeometryUpdatesBlocker blocker(this);
 
     // TODO: All this unmapping, resizing etc. feels too much duplicated from elsewhere
@@ -1850,8 +1846,8 @@ void Client::setBlockingCompositing(bool block)
 
 Client::Position Client::mousePosition() const
 {
-    if (m_decoration) {
-        switch (m_decoration->sectionUnderMouse()) {
+    if (isDecorated()) {
+        switch (decoration()->sectionUnderMouse()) {
             case Qt::BottomLeftSection:
                 return PositionBottomLeft;
             case Qt::BottomRightSection:
@@ -2066,7 +2062,7 @@ NET::WindowType Client::windowType(bool direct, int supportedTypes) const
 
 bool Client::decorationHasAlpha() const
 {
-    if (!m_decoration || m_decoration->isOpaque()) {
+    if (!isDecorated() || decoration()->isOpaque()) {
         // either no decoration or decoration has alpha disabled
         return false;
     }
@@ -2171,7 +2167,7 @@ void Client::showOnScreenEdge()
 #define BORDER(which) \
     int Client::border##which() const \
     { \
-        return m_decoration ? m_decoration->border##which() : 0; \
+        return isDecorated() ? decoration()->border##which() : 0; \
     }
 
 BORDER(Bottom)
@@ -2219,8 +2215,8 @@ bool Client::processDecorationButtonPress(QMouseEvent *event)
 
 void Client::processDecorationButtonRelease(QMouseEvent *event)
 {
-    if (m_decoration) {
-        if (!event->isAccepted() && m_decoration->titleBar().contains(event->pos()) && event->button() == Qt::LeftButton) {
+    if (isDecorated()) {
+        if (!event->isAccepted() && decoration()->titleBar().contains(event->pos()) && event->button() == Qt::LeftButton) {
             m_decorationDoubleClickTimer.start();
         }
     }
diff --git a/client.h b/client.h
index c6b598dd64..1556c64d6b 100644
--- a/client.h
+++ b/client.h
@@ -45,11 +45,6 @@ class KStartupInfoId;
 
 struct xcb_sync_alarm_notify_event_t;
 
-namespace KDecoration2
-{
-class Decoration;
-}
-
 namespace KWin
 {
 
@@ -356,16 +351,7 @@ public:
     bool hasOffscreenXineramaStrut() const;
 
     // Decorations <-> Effects
-    KDecoration2::Decoration *decoration() {
-        return m_decoration;
-    }
-    const KDecoration2::Decoration *decoration() const {
-        return m_decoration;
-    }
     QPointer<Decoration::DecoratedClientImpl> decoratedClient() const;
-    bool isDecorated() const override {
-        return m_decoration != nullptr;
-    }
     void setDecoratedClient(QPointer<Decoration::DecoratedClientImpl> client);
 
     QRect decorationRect() const;
@@ -550,7 +536,7 @@ private:
     Xcb::Property fetchGtkFrameExtents() const;
     void readGtkFrameExtents(Xcb::Property &prop);
     void detectGtkFrameExtents();
-    void destroyDecoration();
+    void destroyDecoration() override;
     void updateFrameExtents();
 
     void internalShow();
@@ -582,7 +568,6 @@ private:
     Xcb::Window m_client;
     Xcb::Window m_wrapper;
     Xcb::Window m_frame;
-    KDecoration2::Decoration *m_decoration;
     QPointer<Decoration::DecoratedClientImpl> m_decoratedClient;
     QElapsedTimer m_decorationDoubleClickTimer;
     QStringList activityList;
diff --git a/events.cpp b/events.cpp
index 508934727b..6324d15032 100644
--- a/events.cpp
+++ b/events.cpp
@@ -1006,10 +1006,10 @@ void Client::leaveNotifyEvent(xcb_leave_notify_event_t *e)
                 shadeHoverTimer->setSingleShot(true);
                 shadeHoverTimer->start(options->shadeHoverInterval());
             }
-            if (m_decoration) {
+            if (isDecorated()) {
                 // sending a move instead of a leave. With leave we need to send proper coords, with move it's handled internally
                 QHoverEvent leaveEvent(QEvent::HoverMove, QPointF(-1, -1), QPointF(-1, -1), Qt::NoModifier);
-                QCoreApplication::sendEvent(m_decoration, &leaveEvent);
+                QCoreApplication::sendEvent(decoration(), &leaveEvent);
             }
         }
         if (options->focusPolicy() == Options::FocusStrictlyUnderMouse && isActive() && lostMouse) {
@@ -1170,7 +1170,7 @@ bool Client::buttonPressEvent(xcb_window_t w, int button, int state, int x, int
         // New API processes core events FIRST and only passes unused ones to the decoration
         return processDecorationButtonPress(button, state, x, y, x_root, y_root, true);
     }
-    if (w == frameId() && m_decoration) {
+    if (w == frameId() && isDecorated()) {
         if (button >= 4 && button <= 7) {
             const Qt::KeyboardModifiers modifiers = x11ToQtKeyboardModifiers(state);
             // Logic borrowed from qapplication_x11.cpp
@@ -1188,9 +1188,9 @@ bool Client::buttonPressEvent(xcb_window_t w, int button, int state, int x, int
                               x11ToQtMouseButtons(state),
                               modifiers);
             event.setAccepted(false);
-            QCoreApplication::sendEvent(m_decoration, &event);
+            QCoreApplication::sendEvent(decoration(), &event);
             if (!event.isAccepted() && !hor) {
-                if (m_decoration->titleBar().contains(x, y)) {
+                if (decoration()->titleBar().contains(x, y)) {
                     performMouseCommand(options->operationTitlebarMouseWheel(delta), QPoint(x_root, y_root));
                 }
             }
@@ -1198,7 +1198,7 @@ bool Client::buttonPressEvent(xcb_window_t w, int button, int state, int x, int
             QMouseEvent event(QEvent::MouseButtonPress, QPointF(x, y), QPointF(x_root, y_root),
                             x11ToQtMouseButton(button), x11ToQtMouseButtons(state), x11ToQtKeyboardModifiers(state));
             event.setAccepted(false);
-            QCoreApplication::sendEvent(m_decoration, &event);
+            QCoreApplication::sendEvent(decoration(), &event);
             if (!event.isAccepted()) {
                 processDecorationButtonPress(button, state, x, y, x_root, y_root);
             }
@@ -1222,7 +1222,7 @@ bool Client::processDecorationButtonPress(int button, int /*state*/, int x, int
     // check whether it is a double click
     if (button == XCB_BUTTON_INDEX_1) {
         if (m_decorationDoubleClickTimer.isValid() &&
-                m_decoration->titleBar().contains(x, y) &&
+                decoration()->titleBar().contains(x, y) &&
                 !m_decorationDoubleClickTimer.hasExpired(QGuiApplication::styleHints()->mouseDoubleClickInterval())) {
             Workspace::self()->performWindowOperation(this, options->operationTitlebarDblClick());
             dontMoveResize();
@@ -1268,7 +1268,7 @@ bool Client::processDecorationButtonPress(int button, int /*state*/, int x, int
 // return value matters only when filtering events before decoration gets them
 bool Client::buttonReleaseEvent(xcb_window_t w, int button, int state, int x, int y, int x_root, int y_root)
 {
-    if (w == frameId() && m_decoration) {
+    if (w == frameId() && isDecorated()) {
         // wheel handled on buttonPress
         if (button < 4 || button > 7) {
             QMouseEvent event(QEvent::MouseButtonRelease,
@@ -1278,8 +1278,8 @@ bool Client::buttonReleaseEvent(xcb_window_t w, int button, int state, int x, in
                               x11ToQtMouseButtons(state) & ~x11ToQtMouseButton(button),
                               x11ToQtKeyboardModifiers(state));
             event.setAccepted(false);
-            QCoreApplication::sendEvent(m_decoration, &event);
-            if (!event.isAccepted() && m_decoration->titleBar().contains(x, y) && button == XCB_BUTTON_INDEX_1) {
+            QCoreApplication::sendEvent(decoration(), &event);
+            if (!event.isAccepted() && decoration()->titleBar().contains(x, y) && button == XCB_BUTTON_INDEX_1) {
                 m_decorationDoubleClickTimer.start();
             }
         }
@@ -1314,10 +1314,10 @@ bool Client::buttonReleaseEvent(xcb_window_t w, int button, int state, int x, in
 // return value matters only when filtering events before decoration gets them
 bool Client::motionNotifyEvent(xcb_window_t w, int state, int x, int y, int x_root, int y_root)
 {
-    if (w == frameId() && m_decoration && !isMinimized()) {
+    if (w == frameId() && isDecorated() && !isMinimized()) {
         // TODO Mouse move event dependent on state
         QHoverEvent event(QEvent::HoverMove, QPointF(x, y), QPointF(x, y));
-        QCoreApplication::instance()->sendEvent(m_decoration, &event);
+        QCoreApplication::instance()->sendEvent(decoration(), &event);
     }
     if (w != frameId() && w != inputId() && w != moveResizeGrabWindow())
         return true; // care only about the whole frame
@@ -1326,9 +1326,9 @@ bool Client::motionNotifyEvent(xcb_window_t w, int state, int x, int y, int x_ro
             int x = x_root - geometry().x();// + padding_left;
             int y = y_root - geometry().y();// + padding_top;
 
-            if (m_decoration) {
+            if (isDecorated()) {
                 QHoverEvent event(QEvent::HoverMove, QPointF(x, y), QPointF(x, y));
-                QCoreApplication::instance()->sendEvent(m_decoration, &event);
+                QCoreApplication::instance()->sendEvent(decoration(), &event);
             }
         }
         Position newmode = modKeyDown(state) ? PositionCenter : mousePosition();
diff --git a/geometry.cpp b/geometry.cpp
index ab73001b0f..0ba2c6dc88 100644
--- a/geometry.cpp
+++ b/geometry.cpp
@@ -1311,7 +1311,7 @@ QSize Client::sizeForClientSize(const QSize& wsize, Sizemode mode, bool noframe)
     // even if they're not set in flags - see getWmNormalHints()
     QSize min_size = tabGroup() ? tabGroup()->minSize() : minSize();
     QSize max_size = tabGroup() ? tabGroup()->maxSize() : maxSize();
-    if (m_decoration != NULL) {
+    if (isDecorated()) {
         QSize decominsize(0, 0);
         QSize border_size(borderLeft() + borderRight(), borderTop() + borderBottom());
         if (border_size.width() > decominsize.width())  // just in case
@@ -2237,9 +2237,9 @@ void Client::changeMaximize(bool vertical, bool horizontal, bool adjust)
     }
 
     // call into decoration update borders
-    if (m_decoration && m_decoration->client() && !(options->borderlessMaximizedWindows() && max_mode == KWin::MaximizeFull)) {
+    if (isDecorated() && decoration()->client() && !(options->borderlessMaximizedWindows() && max_mode == KWin::MaximizeFull)) {
         changeMaximizeRecursion = true;
-        const auto c = m_decoration->client().data();
+        const auto c = decoration()->client().data();
         if ((max_mode & MaximizeVertical) != (old_mode & MaximizeVertical)) {
             emit c->maximizedVerticallyChanged(max_mode & MaximizeVertical);
         }
@@ -2260,7 +2260,7 @@ void Client::changeMaximize(bool vertical, bool horizontal, bool adjust)
         changeMaximizeRecursion = false;
     }
 
-    const ForceGeometry_t geom_mode = m_decoration ? ForceGeometrySet : NormalGeometrySet;
+    const ForceGeometry_t geom_mode = isDecorated() ? ForceGeometrySet : NormalGeometrySet;
 
     // Conditional quick tiling exit points
     if (quickTileMode() != QuickTileNone) {