Tabs on Special:Preferences page and Gadgets have stopped working, unless I comment out require_once("$IP/extensions/Vector/Vector.php"); in LocalSettings.php. Opening any page with Chrome browser, the developer console shows "Uncaught Error: Unknown dependency: jquery.collapsibleTabs" in load.php:150
I tried a re-install but it still has the same problem.
Version: 1.21.x
Severity: major
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=49228