Comment by runarberg
Zoom and Teams are both proprietary software, I doubt any available forks exist, or could exist, for use outside of corporation where they are developed.
I’m guessing they will probably use something built on top of Matrix which is an open protocol maintained by a Community Interest Corporation (CIC) in the UK.
https://www.theregister.com/2025/10/30/france_matrix/
I’m less sure what they will use for video conferencing, but they could do worse then something built on top of WebRTC, which is also an open protocol maintained by W3C, an international standards organization with location in 4 countries (including France and USA).
The French video conferencing tool is called Visio, and is here: https://github.com/suitenumerique/meet. It uses LiveKit for video, but doesn't yet use Matrix - the hope is to make it speak MatrixRTC so it can interop nicely with Tchap (the French fork of Element).