Board Thread:General Discussion/@comment-32625436-20160620011305/@comment-27073024-20160620122715

Correct. Only staff can disable it site-wide on request, but editors can use the __NOWYSIWYG__ magic word to disable it on the page it's used in.

In the past, it has caused the mass deletion of white space in articles, even if the user changed no content (a null edit). I've had it disabled in one of the wikis I manage, so I assumed others have it disabled too.