What is the name of a meeting group chat?

Hi,

I cannot find the name of a meeting group chat.

And it doesn't appear in the list of chats.

I have joined the meeting, used the chat, but there is no trace of it in my activity.

Because the meeting group chat has no name, I cannot add an app to it - like with a regular group chat (not from a meeting).

How can I add an app to a meeting group chat?

Thank you beforehand for your help,

François -