@evanEvan Prodromou 
@mariusormarius Evan, politely, keeping this draft FEP up is doing the community a great miss-service with how it completely butchers client registration and the security issues it has. It really should be withdrawn and revised down to just declaring that we use standard OAuth 2 discovery mechanisms, don't do the Actor mess and instead use CIMDs which are in the OAuth WG standards track (they're adopted by the OAuth WG and will likely become an RFC)
@thisismissemEmelia 👸🏻 @mariusormarius thanks for the note! I'm going to revise it to just document the ActivityPub-native client ID structure. Working out how to negotiate discovery, cimd, dynamic client registration, and client registration properties of the actor will go to an OAuth Profile report for the ActivityPub API task force.
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