It will be open source, end to end encrypted using Signal’s double ratchet encryption protocol, and he plans to make it easy for fediverse platforms to integrate it. The beta will release later this month.
He’s also the creator of https://fedidb.org btw
so this is basically fb messenger but it works with twitter, YouTube and reddit (their federated alternatives mastodon peertube lemmy) and is e2ee!
super cool!