Outlook Add-In for shared mailboxes

Hello all,

do you know if shared mailboxes are supported by Outlook Add-In ("Report to Sophos" button)? It is not explicitly mentioned in documentation, but the button is available in user's mailboxes only.

I have found some thread here with link to Microsoft documentation which says I need to add special section to XML manifest file, but it is not working. It also looks like complicated and non-standard way.

Thank you for any feedback.

Ondrej