When new mail arrives in Outlook, the Windows taskbar icon changes to an icon with an envelope overlay. (See attached screenshot.)

However, this is not the case for the DisplayFusion taskbar, which continues to display the original icon, without the overlay. This is true even if you start Outlook on the main taskbar and then move it to the monitor with the DisplayFusion teaskbar -- DisplayFusion seems to be using a different source for the icon.

Oh, well, I figured it was doing something unusual. Just wanted to make sure it wasn't something that was easily fixable. Office loves to do their own thing with window management, but usually it's Excel that's the problem. Guess they were having so much fun, Outlook decided to join in.

Thanks for getting to the bottom of this issue so quickly.