1,396 votes84 comments · Feature Requests and Feedback » Add-in: Outlook · Flag idea as inappropriate… · Admin →
Thanks for your feedback, the feature is currently in preview. Documentation can be viewed here: https://docs.microsoft.com/en-us/office/dev/add-ins/reference/manifest/supportssharedfolders
We are actively working on making it generally available and will update the status as soon as it is done.Anonymous commented
Apart from shared mbx, our Office365 clients are often require add secondary mailbox mainly by setup delegation, sometimes added manually, if add-in works for those mbx that will be great help.