I'm not sure there is such a thing, but I would like to see some CRDT format being adopted as a first-class data structure inside of nextcloud. This could be built upon for things such as the Whiteboard, but also note-taking applications (Carnet, nextcloud notes...), contacts, and more.

Also, I wish nextcloud talk was using Matrix, there seems to be much duplicated effort between the two, and I am not even sure Nextcloud Talk federates.