[phicoh]

Just curious, which XEP is offline messages?

In Matrix, clients are supposed to implement the full Client-Server API. If a client leaves out e2e then it cannot claim to implement the matrix protocol.

Given that 1.0 of the full matrix protocol was published only a few days ago, it makes sense that anything other than the official implementations are behind. E2e in the official implementation is not that old either.

Even the official implementations need some work to be useful. For example, cross device signing is not there yet.

[Boulth]

> Just curious, which XEP is offline messages?

Simple retaining messages until the client is online was supported since ages, I don't think there is XEP for that but I could be wrong. More elaborate scheme with persistence, multidevice access, paging etc is here: https://xmpp.org/extensions/xep-0313.html

> In Matrix, clients are supposed to implement the full Client-Server API. If a client leaves out e2e then it cannot claim to implement the matrix protocol.

Yes, XMPP has XEP suites that serve the same purpose: https://xmpp.org/extensions/xep-0387.html

[monort]

Just a note - without XEP-0198 you will be losing offline messages if your connection is unreliable. I think most desktop jabber clients still do not support it.