Just like the regular MS Office addins, we would like to create an addin that runs automatically when a mail is selected. There are various use cases for this.

For example, we built an addin that scans email messages when selected and analyzes is and displays messages to the user based on the ,message. This addin is used in the context of phishing mails.

This addin is currently not possible with the current Outlook 365 development model as we want to be proactive and not wait for our users to click on an icon before a mail is processed. In this era of increased ohishing mails, this is a no-brainer.

Also, the pinnable tasks are not a match for this.