On shared mail box, OfficeJS saveAsync() returns a draft ID that is not permitted by the owner's mailbox

Question

Version Affected:

• OfficeJS 1.1.38
• Mac Outlook 16.34 (20020900) Note: This flow use to work up to about April 22, 2020 and this flow currently works on Windows Outlook and Outlook Web Access with our web-addin

Issue:

The Draft ID provided is not accessible by the mailbox owner on MS Graph service

Message returned from Graph:

• code: 404
• message: 404 ErrorInvalidMailboxItemId: "Item Id doesn't belong to the current mailbox."
• status: “failed”

Steps to reproduce:

Add a shared mailbox:

1. Find and Open a shared mailbox

Steps to reproduce:

1. Create a new email in Outlook for Mac
2. In the From field, select the shared mailbox
3. Open and add-in's pane and try to call Office.context.mailbox.item.saveAsync()
4. Pass the result from Office.context.mailbox.item.saveAsync() to

Office.context.mailbox.convertToRestId(
            results[0],
            Office.MailboxEnums.RestVersion.v1_0
          );

5. Use that ID to make a graph call with the mailbox owners graph token . The call errors out with the following message 404 ErrorInvalidMailboxItemId: "Item Id doesn't belong to the current mailbox."