The last relevant message of a conversation. The last relevant message depends on the user: it's the last message the user can see that isn't a system message.
The ID of the message
The avatar URL of the sender
The name of the sender
The person ID of the sender
The timestamp when the message was received by the Collaboration Server
The text of the message
The last relevant message of a conversation. The last relevant message depends on the user: it's the last message the user can see that isn't a system message.