Ah, I might know. If the user has been deleted, but servers are caching the user's Actor record locally, then they might accept a message from that user, provided it was signed with their private key. Is the user's private key accessible from outside of Mastodon somehow? In any case, I may need to periodically update actor records or always fetch them from the source system at receive time to avoid this problem.
So my #ActivityPub server is getting requests from #mastodon users at mastodon.social who no longer exist, by which I mean when my server attempts to fetch their public key (e.g., https://mastodon.social/users/niamonisoberano) it gets a 410 (Gone) response, which I have to assume means their account has been deleted? Except that if I search for that account on Mastodon it shows me that they do exist. It's weird. @niamonisoberano
If you want to run jitsi at scale, please check https://github.com/jitsi/jitsi-videobridge/blob/master/doc/octo.md
Cascaded SFUs will allow your conference calls to scale a lot better :)
Also recommended, the following talk if you want to understand the concept:
ZOMG That message actually federated to my app correctly!
Night Approach into Crystal (KMIC) https://peertube.koehn.com/videos/watch/85789873-7e7e-4b24-a87d-0f5cf6b669da
Lookout Mountain timelapse https://peertube.koehn.com/videos/watch/b1ea1b12-47b0-43dc-9e47-2c382d0c7c11
The sounds of my childhood. https://youtu.be/v3O9vNi-dkA