Defines a min channel that was seen in a certain message of a certain chat.
inputChannelFromMessage#5b934f9d peer:InputPeer msg_id:int channel_id:long = InputChannel;
|peer||InputPeer||The chat where the channel was seen|
|msg_id||int||The message ID in the chat where the channel was seen|
|channel_id||long||The channel ID|
In some situations user and channel constructors have reduced set of fields present (although id is always there) and min flag set.