diff --git a/core/misc/vertical-tabs.js b/core/misc/vertical-tabs.js
index bb0c0c4..02c4a88 100644
--- a/core/misc/vertical-tabs.js
+++ b/core/misc/vertical-tabs.js
@@ -43,7 +43,6 @@
         var $this = $(this).addClass('vertical-tabs__panes');
         var focusID = $this.find(':hidden.vertical-tabs__active-tab').val();
         var tab_focus;
-        var $tabPaneSet = $(this);
 
         // Check if there are some details that can be converted to
         // vertical-tabs.
@@ -54,13 +53,13 @@
 
         // Create the tab column.
         var tab_list = $('<ul class="vertical-tabs__menu"></ul>');
-        $tabPaneSet
+        $this
           .wrap('<div class="vertical-tabs clearfix"></div>')
           .before(tab_list)
           // If there are no visible tab panes, hide the whole vertical-tabs
           // area.
           .on('updateTabPaneSet', function() {
-            var tab_set = $tabPaneSet.parent();
+            var tab_set = $this.parent();
             tab_set.show();
             var $panes = $('> details:visible', this);
             if ($panes.length == 0) {
@@ -101,7 +100,7 @@
                     vertical_tab.item.show();
                     vertical_tab.updateSummary();
                   }
-                  $tabPaneSet.trigger('updateTabPaneSet');
+                  $this.trigger('updateTabPaneSet');
                   // Don't bubble this up to the default handler.
                   e.stopPropagation();
                 }