====== adv.groupID ======
wrtc.adv.groupID is a string property containing a group call's unique group ID. Each group call shall have a unique group ID shared between all group call participants.

If you don't set it to anything a random ID will be applied when group call starts.

===== Value =====
String containing group call's unique ID.

===== Usage =====
Usually you do not need to set wrtc.adv.groupID. If you however want to set it to a specific value you must do so before starting the group call, and you are not allowed to change wrtc.adv.groupID during the group call.