--- a/widget/src/windows/nsWindow.cpp
+++ b/widget/src/windows/nsWindow.cpp
@@ -7124,17 +7124,16 @@ void nsWindow::UpdateWindowInternal(HWND
   if (aWnd) {
 #ifdef MOZ_IPC
     if (mWindowType == eWindowType_plugin) {
       PluginInstanceParent* instance = reinterpret_cast<PluginInstanceParent*>(
         ::GetPropW(aWnd, L"PluginInstanceParentProperty"));
       if (instance) {
         if (!instance->CallUpdateWindow())
           NS_ERROR("Failed to send message!");
-        ValidateWindow(aWnd, NULL);
         return;
       }
     }
 #endif
     VERIFY(::UpdateWindow(aWnd));
   }
 }