I found that during a video call, the local retrovision thumbnail is cropped, so it doesn’t show locally some regions that were conversely visible on the peer client. I would say this is somewhat a privacy flaw. One should be able to tell exactly what picture is transmitted to the peer, and be assured of what is out of sight.
This is on Android 15. Don’t know if this happens always or if it depends on the peer’s screen resolution. It may be the WebRTC implementation that is responsible for this, but maybe they can be influenced to fix the problem so that both endpoints have the same picture?