User blog comment:Kirkburn/Technical Update: November 25, 2015/@comment-1757994-20151128013042

Also note that we change hundreds of tiny details every week, so these are just the highlights. One of the changes this week (uncertain if it was Tuesday or Thursday) is that css and js from mercury.nocookie.net no longer appears to be loaded in the WikiaMobile skin. So: Glitch? Or are these changes really intended?
 * 1) Although Mercury css is not loaded, several other css files are loaded, including personal common.css. I think the ability to add personal styling to WikiaMobile is not a "tiny detail."
 * 2) The Mercury JS hacks to many methods are no longer run (e.g., the hack to document.head.appendChild which automatically threw an error if you run it from the console).