Hi @Fabrice Lefebvre ,
Does anyone else with Catalina have the same issue in your organization?
Can this user share screen normally in Teams meeting?
Does this issue persist if you use Teams web client?
Please make sure again if you have ticked Microsoft Teams in the System Preferences->Security and Privacy->Screen Recording. For more details about setting on Mac, you can learn it from:
https://www.uvm.edu/it/kb/article/macos-allow-screen-sharing/
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