Hi! I’m Ciarán (or Sporiff, as I’m known online). I’m a technical writer and one of the maintainers of Funkwhale.
I’m currently working on expanding ActivityPub support in Funkwhale by writing up new feature specifications and federation overviews for developers to follow and implement.
I’m looking forward to keeping up with the discussions here a bit more and learning about best practices (and fun solutions to the harder issues!).
I reported this ActivityPub compatibility problem a while back: Serving ActivityPub objects (#2021) · Issues · funkwhale / funkwhale · GitLab
It would be nice if you look into it (maybe it’s already fixed, I can’t verify because the server in question is gone)
Thanks for the report! I’ve confirmed this is still an problem and updated the issue. I’ll bring it up with the team to see who has scope to pick it up.
Funkwhale also has a problem dealing with servers that have “authorized_fetch” on. See the result of:
The required dataflow should look like this
Interesting! This could explain some issues we see in our Glitchtip instance. I’ll take a note of these and create an issue for it to make sure we cover it in our upcoming work 
Let me know if you need any review or feedback on trust & safety things. Always happy to help.