Context
When a user clicks on "reply" or "reply all" in Outlook, add-ins should be able to retrieve the original recipients (To, CC, BCC) of the mail item as they were set when the reply or reply all action was initiated, regardless of any user edits to the recipient list afterwards.
Currently, office-js returns an updated recipient array if the user quickly changes the recipients after clicking "reply" or "reply all". As a result, there is no way for an add-in to determine what the original recipients of the mail item were. This makes it difficult to compare and process recipient changes.
Steps to reproduce
- User receives an email with recipients A, B, and C.
- User clicks "Reply All".
- Before sending, user deletes B and adds D to the recipients.
- Office-js API only returns the new recipient array (A, C, D), with no way to access the original recipients (A, B, C).
This issue affects add-ins that need to compare the original recipients of an email to the recipients after user edits, for processing or compliance reasons. Having access to the original recipient list would make it possible to implement robust recipient management features. Currently, even if you store these recipients during onMessageCompose event, it is possible to have wrong data there if user changes recipients right away after clicking reply / reply all / forward.