diff --git a/widget/public/nsIWidget.h b/widget/public/nsIWidget.h
index 7e7cd80f024..dd0db2a34ed 100644
--- a/widget/public/nsIWidget.h
+++ b/widget/public/nsIWidget.h
@@ -115,7 +115,11 @@ enum nsWindowType {
   // child windows (contained inside a window on the desktop (has no border))
   eWindowType_child,
   // windows that are invisible or offscreen
-  eWindowType_invisible
+  eWindowType_invisible,
+  // plugin window
+  eWindowType_plugin,
+  // java plugin window
+  eWindowType_java
 };