Index: /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp
===================================================================
--- /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp	(revision 54014)
+++ /trunk/src/VBox/Frontends/VirtualBox/src/runtime/UIMachineView.cpp	(revision 54015)
@@ -439,8 +439,9 @@
                      * the viewport through IFramebuffer::NotifyUpdate): */
                     display().InvalidateAndUpdate();
-                    /* Reapply machine-view scale-factor if necessary: */
-                    applyMachineViewScaleFactor();
                 }
             }
+            /* Reapply machine-view scale-factor if necessary: */
+            if (m_pFrameBuffer)
+                applyMachineViewScaleFactor();
             break;
         }