diff --git a/app/scripts/fetch_xulrunner b/app/scripts/fetch_xulrunner
index 28c7a49d68..065970ab22 100755
--- a/app/scripts/fetch_xulrunner
+++ b/app/scripts/fetch_xulrunner
@@ -512,6 +512,9 @@ function modify_omni {
           dropmarker.className = "toolbarbutton-menu-dropmarker";
           this.appendChild(dropmarker);
         }' chrome/toolkit/content/global/elements/toolbarbutton.js
+	# Let clicks on the dropmarker pass through to the toolbarbutton, which only opens its menu
+	# when it's the original event target, as xul.css did when Firefox created the dropmarker
+	echo '.toolbarbutton-menu-dropmarker { pointer-events: none; }' >> chrome/toolkit/content/global/xul.css
 
 	# Remove non-native text input styles
 	remove_between 'html\|input\:where\(' '^}' chrome/toolkit/skin/classic/global/global-shared.css