diff --git a/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js b/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js
index fb35482f0..6dc47ba27 100644
--- a/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js
+++ b/wagtail/wagtailadmin/static_src/wagtailadmin/js/core.js
@@ -82,9 +82,9 @@ $(function() {
     });
 
     /* close all dropdowns on body clicks */
-    $(document).on('click', function(e) {
-        var relTarg = e.relatedTarget || e.toElement;
-        if(!$(relTarg).hasClass('dropdown-toggle') && !$(relTarg).closest('.dropdown').length){
+    $(document).on('click', function(e){
+        var targ = e.target;
+        if(!$(targ).hasClass('dropdown-toggle') && !$(targ).closest('.dropdown').length){
             $('.dropdown').removeClass('open');
         }
     });