diff --git a/xpfe/global/resources/skin/xul.css b/xpfe/global/resources/skin/xul.css
index 907b9839130..e03ea743bc0 100644
--- a/xpfe/global/resources/skin/xul.css
+++ b/xpfe/global/resources/skin/xul.css
@@ -587,6 +587,10 @@ xpmenubar > xpmenu[menuactive="true"] {
   color:#333366;
 }
 
+xpmenubar > xpmenu[menuactive="true"][open="true"] {
+  border: 1px inset;
+}
+
 xpmenuchildren > xpmenu[menuactive="true"] {
   background-color: #666699;
   color: white;