Have you seen nostr:npub108pv4cg5ag52nq082kd5leu9ffrn2gdg6g4xdwatn73y36uzplmq9uyev6's mostr ?
I'm thinking a bit more about how to bridge to the Fediverse. One of the problems is that ActivityPub doesn't use public keys for identity. Instead it relies on a URI, and so ultimately on the https certificate of the instance owner.
https://www.w3.org/TR/activitypub/#actors
This means that, when seen from the Nostr side, there could be multiple copies of the same Fediverse user, depending on which bridge their messages went across. And it's non-trivial to verify the original message wasn't tampered with by the bridge (though anyone can do so, by comparing).
So we could propose additional an optional public key to the standard. It would allow folks to sign their own message and would give Fediverse folks a unique identifier, independent who builds the bridge to Nostr.
But:
1) Changing a standard is work and could take years
2) Even with a public key in place, and even assume it's a curve Nostr clients can deal with, ActivityPub message are probably signed in some particular way, different from regular Nostr posts. So Nostr clients would still need special-case handing for this.
Discussion
Yes, I use it :-) The above brainstorm came from me opening this issue: https://gitlab.com/soapbox-pub/mostr/-/issues/54
Mostly blocked by fediverse instances. They are so insecure about their protocol.
Is there an easy way to tell which instances block vs which ones are just not very well synced? Or is it considered a feature to be intransparent about censorship?
I often can't find myself on other instances. Sometimes I follow someone but my replies seem to get blackholed / denyholed.
But here everything shows up smoothly: https://gleasonator.com/@8685ebef665338dd6931e2ccdf3c19d9f0e5a1067c918f22e7081c2558f8faf8@mostr.pub/posts/AYzmgHNMCYBNzGlvKS
Maybe the bridge can reply (from its own account) if it detect a message was blocked? Then instead of thinking your Fediverse friend hates you, you can tell them (out of band) to evacuate.
Also, do DM's actually make it accross the bridge? Obviously they'd lose e2e encryption. If not, again there should be some auto-reply from the bridge.