Big regression introduced with this change: the diff that shows to FlaggedRevs reviewers when there are any unreviewed changes can’t be shown anymore because diff toggle gets hidden upon loading. Some reviewers probably won’t be happy with this. I don’t know how we’re going to fix this if there won’t be any deployments for 2 weeks, though.
(Ideally, this old code shouldn’t use bootleg toggles and should use jquery.makeCollapsible, but alas.)
Reproduce (look for #mw-diff-toggle in browser console):