User blog comment:Kirkburn/Technical Update: September 2, 2015/@comment-5973717-20150904162145/@comment-166269-20150905033552

@Nerfmaster8
 * The removal of the ability for admins to edit arbitrary user CSS/JS mitigates this attack vector, of course, but the addition of a user preference for enabling user JS in the first place, and defaulting it to disabled, allows Wikia to keep their options open going forward, so that they might later be able to reenable admin editing of these pages, to some degree at least, or perhaps even introduce a more general system that could allow non-admins to edit these pages under specific circumstances.