I guess newer Prosody supports this and much more out of the box but the generic configuration instructions I used are here: https://serverfault.com/questions/835635/what-prosody-module...
> The problem with omemo, jingle, etc. is that you have makes sure that the XMPP components you use support them. It would be fine if all popular implementations support those features, but that's not the case.
Isn't this also the case with Matrix that no implementations except the official ones support E2E encryption?