%4tnRTr0CjsZyjS32mNFMj0XkQSz6uGxfDePB5/B/1G4=.sha256recently came across https://cwtch.im/ tl;dr: groups for riccochet.
my main gripe with riccochet is that is only works when both parties are online and that it fully trusts tor's transport crypto. Will have to check out how both of these problems are handled in cwtch.
Anonymous, Decentralized, Metadata-Resistant Group Messaging
Warning: Cwtch is an experimental prototype. Please do not use it for anything where security, privacy, or anonymity is critical.
Communications metadata is known to be exploited by various adversaries to undermine the security of systems, to track victims and to conduct large scale social network analysis to feed mass surveillance. Metadata resistant tools are in their infancy and research into the construction and user experience of such tools is lacking.
Cwtch is an extension of the metadata resistant protocol Ricochet to support asynchronous, multi-peer group communications through the use of discardable, untrusted, anonymous infrastructure.