Just to keep things updated here, we will add a per-Cloudron configuration variable in the next Cloudron release to give the OpenID provider a customizable name. Then the apps like Mediawiki which support that kind of customization will pick this up by default.

@SamGreenwood to install on the root domain, you can just leave the subdomain field empty to have it moved there.

@jtippetts I have to check your instance to see why it's not working. Can you write to us at support@cloudron.io ?