In user reported settings, admins can select Monitor reported messages in Outlook > Use a non-Microsoft add-in button. In the Reported message destination section, select Microsoft and my reporting mailbox, and then provide the email address of the internal Exchange Online mailbox where user-reported messages by the non-Microsoft add-in are routed to. Microsoft analyzes these reported messages and provides result on the User reported tab of Submissions page at https://security.microsoft.com/reportsubmission?viewid=user.