diff --git a/core/modules/system/system.module b/core/modules/system/system.module
index 0d472e5..87f7606 100644
--- a/core/modules/system/system.module
+++ b/core/modules/system/system.module
@@ -1406,7 +1406,7 @@ function system_library_info() {
     'title' => 'Drupal tabbing manager',
     'version' => VERSION,
     'js' => array(
-      'core/misc/tabbingmanager.js' => array('group', JS_LIBRARY),
+      'core/misc/tabbingmanager.js' => array('group' => JS_LIBRARY),
     ),
     'dependencies' => array(
       array('system', 'jquery'),