Hello @Rolf Nygård ,
Welcome to Microsoft QnA.
May I know what is the version of Windows Desktop Client you are using?
To use Microsoft Teams Give and Take Control, the minimum Windows Desktop Client version 1.2.2924 is required to enable the feature on Azure Virtual Desktop. You can also refer to the same here in this blog post -> Microsoft Teams Give and Take Control is now generally available on Azure Virtual Desktop.
Also, could you please verify that the user is selecting the Teams icon from within the session host, and not from the host's taskbar ? (Sometimes we see users might get confused as the host's taskbar appear below the session host because of the session host window not being in full screen mode).
Could you confirm the above two checks and then respond back to me and tag me here, and I shall get back to you on the further steps we can do to fix it. :)
Thanks & Regards,
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