View Message source
Remove the deep link function by double click on the message. It is so annoying. If I forget and double click on the message, I get the deep link popup window which takes a century to open.
Callie Prinari commented
In the past, View Message Source was possible to access just by selecting the email WITHOUT opening it. This was an excellent tool smartly located esp. for reporting spam. Now, it's accessible only by opening the spam which might be risky. This was the main reason for using Outlook instead of any other. Please bring it back where it was in the past.