Thread:ChromeCircus/@comment-3218221-20171014152025/@comment-3218221-20171016100552

The interesting thing is that the modernization of Headers/Top Nav, etc. (or one of the technical updates around that time) made it so that creating a new page via the top-right icon would have users default to the classic editor instead of the visual editor, which is evidently not what happened to you at all. I think I remember quite a few people complaining and asking how they could switch it back...

The Baccano! wiki's top-right "create a page" button definitely defaulted to the visual editor before the June 12th rollout.

If you go to Special:Preferences you can change which editor is default for you, though it affects edits and not just what defaults for creating a new page.

Ah...yep. Rooted around in the technical updates archive - one week after the rollout of the new headers, the June 19th list of updates included one making it so that "add a new page" would respect a user's editor preferences. Definitely a response to the multiple users in the forums upset with the button defaulting to classic.

Edit:  This user actually had issues with editor defaulting to classic all the time before the rollout of the new headers, which another user thought might have been a javascript error. I'm going to assume that in this case it's a matter of just editing your editing preferences, but I thought it was worth linking to for reference's sake.