diff --git a/widget/src/xpwidgets/nsBaseWidget.h b/widget/src/xpwidgets/nsBaseWidget.h
index cb3f13ca78c1..52d72118934c 100644
--- a/widget/src/xpwidgets/nsBaseWidget.h
+++ b/widget/src/xpwidgets/nsBaseWidget.h
@@ -133,7 +133,7 @@ protected:
       NS_DECL_ISUPPORTS
 
       Enumerator();
-      ~Enumerator();
+      virtual ~Enumerator();
 
       NS_IMETHOD First();
       NS_IMETHOD Last();