diff --git a/plugins/scenes/opengl/scene_opengl.h b/plugins/scenes/opengl/scene_opengl.h
--- a/plugins/scenes/opengl/scene_opengl.h
+++ b/plugins/scenes/opengl/scene_opengl.h
@@ -220,6 +220,7 @@
 
 class OpenGLWindowPixmap : public WindowPixmap
 {
+    Q_OBJECT
 public:
     explicit OpenGLWindowPixmap(Scene::Window *window, SceneOpenGL *scene);
     virtual ~OpenGLWindowPixmap();
diff --git a/plugins/scenes/qpainter/scene_qpainter.h b/plugins/scenes/qpainter/scene_qpainter.h
--- a/plugins/scenes/qpainter/scene_qpainter.h
+++ b/plugins/scenes/qpainter/scene_qpainter.h
@@ -86,6 +86,7 @@
 
 class QPainterWindowPixmap : public WindowPixmap
 {
+    Q_OBJECT
 public:
     explicit QPainterWindowPixmap(Scene::Window *window);
     virtual ~QPainterWindowPixmap();
diff --git a/scene.h b/scene.h
--- a/scene.h
+++ b/scene.h
@@ -388,8 +388,9 @@
  * This class is intended to be inherited for the needs of the compositor backends which need further mapping from
  * the native pixmap to the respective rendering format.
  */
-class KWIN_EXPORT WindowPixmap
+class KWIN_EXPORT WindowPixmap : public QObject
 {
+    Q_OBJECT
 public:
     virtual ~WindowPixmap();
     /**
@@ -473,7 +474,7 @@
     KWayland::Server::SurfaceInterface *surface() const;
 
 protected:
-    explicit WindowPixmap(Scene::Window *window);
+    explicit WindowPixmap(Scene::Window *window, QObject *parent = nullptr);
     explicit WindowPixmap(const QPointer<KWayland::Server::SubSurfaceInterface> &subSurface, WindowPixmap *parent);
     virtual WindowPixmap *createChild(const QPointer<KWayland::Server::SubSurfaceInterface> &subSurface);
     /**
diff --git a/scene.cpp b/scene.cpp
--- a/scene.cpp
+++ b/scene.cpp
@@ -979,15 +979,17 @@
 //****************************************
 // WindowPixmap
 //****************************************
-WindowPixmap::WindowPixmap(Scene::Window *window)
-    : m_window(window)
+WindowPixmap::WindowPixmap(Scene::Window *window, QObject *parent)
+    : QObject(parent)
+    , m_window(window)
     , m_pixmap(XCB_PIXMAP_NONE)
     , m_discarded(false)
 {
 }
 
 WindowPixmap::WindowPixmap(const QPointer<KWayland::Server::SubSurfaceInterface> &subSurface, WindowPixmap *parent)
-    : m_window(parent->m_window)
+    : QObject(parent)
+    , m_window(parent->m_window)
     , m_pixmap(XCB_PIXMAP_NONE)
     , m_discarded(false)
     , m_parent(parent)
@@ -1086,6 +1088,12 @@
                 if (p) {
                     p->create();
                     children << p;
+                    QObject::connect(subSurface->surface().data(), &KWayland::Server::SurfaceInterface::sizeChanged, this, [this, p] {
+                        if (m_children.removeOne(p)) {
+                            // If it was in the stack, it existed. Delete it now so we don't leak.
+                            delete p;
+                        }
+                    });
                 }
             }
         }