in beta still but https://briarproject.org/download-briar-desktop/ is worth a look
16 karma · joined November 15, 2021
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.
And a 2-party QR code protocol for adding contacts in person: https://code.briarproject.org/briar/briar-spec/blob/master/p...
In short, both these methods of adding contacts require both parties to actively add each other in the same time period. So even if you post your briar contact code publicly, only the contacts you are adding as well will be able to connect with you.