How to know if a FaceTime call is active?

The GroupSession API doesn't seem to expose any method for determining whether there is active FaceTime call.

Any suggestions on how one might check this?

(I can't use groupSession.activeParticipants, as this data is only available once a SharePlay session has started. I need to know the existence of a FaceTime call prior to the user starting a SharePlay session).

GroupActivity.prepareForActivation() will be activationDisabled and GroupStateObserver.isEligibleForGroupSession will be false if there is no FaceTime call.

How to know if a FaceTime call is active?
 
 
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