Call duration, in seconds; for left calls only.
Optional is_True, if the call is active, i.e. the called user joined the call.
Optional is_True, if the call is a video call.
Identifiers of some other call participants.
Optional was_True, if the called user missed or declined the call.
A message with information about a group call not bound to a chat. If the message is incoming, the call isn't active, isn't missed, and has no duration, and getOption("can_accept_calls") is true, then incoming call screen must be shown to the user. Use joinGroupCall to accept the call or declineGroupCallInvitation to decline it. If the call become active or missed, then the call screen must be hidden. Subtype of MessageContent.