Support XEP-0280 “Message Carbons”
Please add support for XEP-0280 “Message Carbons”. It allows clients to subscribe to carbon copies of messages sent to/from other clients. Very useful in a mobile environment as it enables the user to continue a conversation they had on another device and visa versa without requiring the mobile device to be connected to the server at all times.
This should require little work on the side of the client.
Testing notes: The most recent versions of Gajim (client) and Prosody (server) support XEP-0280.