Ticket #12949: nav_menu_term_url_bug.diff

wp-includes/nav-menu.php

@@ -272 +272 @@
                         $menu_item->append = strtolower( $object->singular_label );
 
                         $menu_item->title = $menu_item->name;
-                        $menu_item->url = get_term_link( $menu_item, $menu_item_object );
+                        
+                        $term_url = get_term_link( $menu_item, $menu_item_object );
+                        $menu_item->url = !is_wp_error( $term_url ) ? $term_url : '';
                         $menu_item->target = '';
                         $menu_item->attr_title = '';
                         $menu_item->description = '';