diff --git a/notebook/static/notebook/js/toolbar.js b/notebook/static/notebook/js/toolbar.js
index 7ca2e390c..8b85c0b55 100644
--- a/notebook/static/notebook/js/toolbar.js
+++ b/notebook/static/notebook/js/toolbar.js
@@ -118,6 +118,7 @@ define([
             // END IIFE
         }
         $(this.selector).append(btn_group);
+        return btn_group;
     };
 
     ToolBar.prototype.style = function () {