User blog comment:Rupert Giles/Layout Changes: Breakpoints and Typography/@comment-8695373-20150519112556/@comment-452-20150519114828

I have not tried to "revert it": I prefer to see use 100% width, so my edits over the last 2 days have only been to make it look exactly the way it did for me yesterday, not for you yesterday.

However, I can see no reason why CSS to simulate reverting it would not be possible.