--- a/layout/xul/nsMenuBarListener.cpp
+++ b/layout/xul/nsMenuBarListener.cpp
@@ -206,17 +206,18 @@ nsMenuBarListener::KeyPress(nsIDOMEvent*
   InitAccessKey();
 
   if (mAccessKey)
   {
     // If accesskey handling was forwarded to a child process, wait for
     // the mozaccesskeynotfound event before handling accesskeys.
     WidgetKeyboardEvent* nativeKeyEvent =
       aKeyEvent->WidgetEventPtr()->AsKeyboardEvent();
-    if (nativeKeyEvent && nativeKeyEvent->mAccessKeyForwardedToChild) {
+    if (!nativeKeyEvent ||
+        (nativeKeyEvent && nativeKeyEvent->mAccessKeyForwardedToChild)) {
       return NS_OK;
     }
 
     nsCOMPtr<nsIDOMKeyEvent> keyEvent = do_QueryInterface(aKeyEvent);
     uint32_t keyCode, charCode;
     keyEvent->GetKeyCode(&keyCode);
     keyEvent->GetCharCode(&charCode);