Suggestion for the frontpage to include https://armada.buzz there, its an open source discord alternative by the makers of Ditto (already listed) that primarily focuses on Concord (The same protocol Vector uses which is also already listed).
Armada’s WebXDC capabilities are currently ahead of Vector since it supports the regular sendUpdate as well as browser based joinRealtimeChannel that still uses Iroh relays.
Its WebXDC support was partially developed by the Vector developer with the aim of being cross compatible, so if you join a realtime channel WebXDC app on one you end up in the same lobby on the other. I then extended that to the DM’s so they would have WebXDC as well.
Aside from the browser version it also has downloadable apps : Armada
Its AGPLv3 licensed with the source code available here : gitworkshop - Decentralized Git