Black sharing desktop or application doesn' work on Debian buster

When I try to share my screen or a window on Jitsi the shared area is always black.
Same issue on Firefox 78.4.1esr (64 bits) or Chrome Version 86.0.4240.198 (Build officiel) (64 bits).
No problem on Ubuntu. For the same hardware configuration I’ve got the issue on Debian Buster.

Any clues ?