Iris now supports secret chats that don't leak metadata, implementing the https://hrfbounties.org/ bounty #3. It works also for group messaging.

It's a quick & dirty solution, but works. A shared nostr account is created for the secret chat / group. Its nsec can be shared via link, qr code or invite message from a single-use anonymous account.

Users can then communicate using the shared account's messages-to-self. Iris signs the inner messages with your own key, but the arrangement could be used for anonymous group messaging as well.

I'll also add inner message encryption at some point, so you can ensure that only certain group participants can read the message.

This arrangement doesn't introduce any new event kinds and works also in clients that haven't implemented a special UX for it. You can just log in with the nsec and message yourself.

I had to disable the Iris social graph filter to let invites through, so now Iris DMs are open to spam again, but I'll try to figure out a better solution.

As always, the UX needs a lot of attention, but I believe here's an MVP.