Hi there,
Just letting you know this issue reported to Cachyos with Brave Browser also affects OpenMandriva: https://www.reddit.com/r/cachyos/comments/1ki23wt/solved_screen_sharing_in_ms_teams_not_working/
Seems like the “Plasma Integration” extension breaks the screensharing feature from XDG-Portal. By disabling this extension, it works fine.
Kind regards