Make SurfaceItemX11 schedule a repaint if the shape changes

src/surfaceitem_x11.cpp

@@ -18,7 +18,7 @@ SurfaceItemX11::SurfaceItemX11(Window *window, Item *parent)
     connect(window, &Window::bufferGeometryChanged,
             this, &SurfaceItemX11::handleBufferGeometryChanged);
     connect(window, &Window::geometryShapeChanged,
-            this, &SurfaceItemX11::discardQuads);
+            this, &SurfaceItemX11::handleGeometryShapeChanged);
 
     m_damageHandle = xcb_generate_id(kwinApp()->x11Connection());
     xcb_damage_create(kwinApp()->x11Connection(), m_damageHandle, window->frameId(),
@@ -123,6 +123,12 @@ void SurfaceItemX11::handleBufferGeometryChanged(Window *window, const QRect &ol
     setSize(window->bufferGeometry().size());
 }
 
+void SurfaceItemX11::handleGeometryShapeChanged()
+{
+    scheduleRepaint(boundingRect());
+    discardQuads();
+}
+
 QRegion SurfaceItemX11::shape() const
 {
     const QRect clipRect = window()->clientGeometry().translated(-window()->bufferGeometry().topLeft());

src/surfaceitem_x11.h

@@ -37,6 +37,7 @@ public:
 
 private Q_SLOTS:
     void handleBufferGeometryChanged(Window *window, const QRect &old);
+    void handleGeometryShapeChanged();
 
 protected:
     SurfacePixmap *createPixmap() override;