One thing that seemingly supports Persona is Mailman 3. So the Persona extension is still worth working on, unless adding OAuth support to Mailman 3 is less effort. https://meta.wikimedia.org/wiki/Talk:Discourse#Wikimedia_account_support
Wikis using it seem to include https://sudoroom.org/ and http://arabdigitalexpression.org ; is there a way to know how many users? Are private wikis more likely to have an advantage in using Persona compared to other methods?
Nemo