Just added (#)ReplacingMatrix to my profile of course this is minus the E2EE...so in a way maybe this makes it like "Discord"...although it's a slight workaround...
ie. you need to send someone a mention to an etherpad...
ie. https://etherpad.wikimedia.org/p/MastEthcord61035492/timeslider#257
(#)MastEthcord is what you think it is. Name inspired by "Dis cord" and uses only Mastodon+Etherpad, nothing else necessary!
No encryption, all are public notes/chats.
