Sometimes it is nice to know if the other user you are in a chat with is replying right now. It appears that with Microsoft Teams you will get a notification of “User is typing” (as shown above) only if you are in a “Chat”, that is, a one to one chat as opposed to a conversation in a “Team”.
If you are following a chat in a “Team” you will not see a “[User] is typing” indicator, you will just see “New Message[s]” as shown above.
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