[giphyman]

A Briar user can either create a new forum, or get invited via a Briar contact that is already in an existing forum. There's some more info on this topic in Briar's user manual if you're interested: https://briarproject.org/manual/

Briar also has the ability to introduce contacts to each other, so while it doesn't support totally public forums, you can spread information between contacts fairly effectively.