When users want to login using Wikimedia SUL, they get an unclear and somewhat scary dialog text -- see https://www.mediawiki.org/wiki/Talk:Phabricator/versus_Bugzilla#SUL
Submitted to https://bugzilla.wikimedia.org/show_bug.cgi?id=71888 because (I believe) this is an OAuth extension problem (MediaWiki's extension, not the one developed by @mmodell for Phabricator). Please correct me if I'm wrong.
Something that we could improve on our side is the "phabricator-production" denomination. "phabricator.wikimedia.org" would sound more clear and friendly.