We set up a bridge between the Lemmy.world General Matrix room and the Public-1 channel on the Lemmy World discord server yesterday. It’s not perfect as emoji reactions aren’t visible and some minor things like how it handles edited messages but other than that it seems to be working well.
Now people on both chat clients can interact with eachother!
Matrix is federated, supports private channels, encryption, and cryptographic user signatures. It’s basically un-attackable (unless you open a channel to everyone).