User blog comment:BertH/Fluid layout has arrived/@comment-4727448-20131205001715/@comment-957747-20131205002841

@Scrawland, if you're seeing wikis with odd background (affected by this change) please send them to Special:Contact. This update makes a change to the way backgrounds are handled. In most cases, the oddity is from the fact that the background is done through custom CSS and not through the ThemeDesigner. I would suggest reading this thread that covers that issue.

@Miskos3, personally, I create articles based on the lowest denomination a let users with bigger screens enjoy the extra space. To do this, create pages based on the 'minimal size' when previewing pages and edit accordingly. Chances are, this won't change your editing style from before the change to now.