I think https://call.element.io/ https://call.element.io/ works like that. Calls are encrypted and the client includes screen sharing and all the standard video

I think https://call.element.io/ https://call.element.io/ works like that. Calls are encrypted and the client includes screen sharing and all the standard video conferencing features. Jitsi Meet is also a classic example of this, though these days it requires at least one logged-in "moderator" user to work.