Hi @Loïc
According to our test, there is an issue where new Teams is not visible in the defender for endpoint.
In our Microsoft Feedback forum, there are users who have reported the same issue. Please cast a vote to get this feature as soon as possible. Many features of our current products are designed and upgraded based on customer feedback. As such demand increases, this issue is likely to be released in the future.
If you want to monitor Teams for vulnerabilities, you can try to use Windows Defender Application Control application tagging policies for New Teams.
Thanks for your understanding and support.
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