User blog comment:Rappy 4187/Technical Update: May 4, 2015/@comment-4714517-20150506064529/@comment-1038387-20150507120637

Yes, preview buttons got changed months ago. They did that so people would be more conscious about mobile users. Which are 50 percent or so of Wikia views. Unfortunately, we still can't see those stats for one particular wiki.

I don't recall them saying that feature was subject to change in the future.