Concurrent RCV Meetings - display warning to host/attendee if they are already in another RCV meeting

I love the ability to join multiple RCV meetings, it has some useful use-cases which are now catered for....however, I have on occasion joined a meeting without realising I was still in another meeting which led to some embarrassment.

Would be good to have a warning pop-up alerting me that I am already in another RCV meeting and to check if I do wish to start/join another one.