diff --git a/scene_opengl.cpp b/scene_opengl.cpp
index 27c9ab8790..77aec3c0c9 100644
--- a/scene_opengl.cpp
+++ b/scene_opengl.cpp
@@ -398,7 +398,7 @@ qint64 SceneOpenGL::paint(QRegion damage, ToplevelList toplevels)
         glReadBuffer(GL_FRONT);
         copyPixels(displayRegion - validRegion);
         glReadBuffer(GL_BACK);
-        damage = displayRegion;
+        validRegion = displayRegion;
     }
 #endif