provide an event to let Outlook Add-in respond to a change in the message being written (for example message body, To, Cc and Bcc lists)
For example if the user adds further To, Cc or Bcc Addresses, it would be advantageous if the add-in could react to it and display relevant data.
Thanks for your feedback! This is in our backlog but lower priority than a few other features. We’ll keep you posted with updates.
Office Extensibility Team
Rick Goud commented
Is there an update on this issue? Would be great if there is no manual trigger needed to activate an add-in in compose mode just like in read mode. Why is the priority low given te relatively high number of votes? Is there an overview what then has higher priority?
I subscribe to this idea also. It would be really helpful.