While it makes no sense from UX point of view, MG seems to mean "Meeting Guest" (and it's one of the real participants, not a suspicious 'extra participant').
Teams call - extra "person" appearing on call.
Toneatto, Anita
15
Reputation points
A staff member has a Teams call with a client. On the client's end, it looks like another participant is in the call - appearing as initials either UU or MG. However, there are no extra participants in the meeting.
Microsoft Teams | Microsoft Teams for business | Other
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