When a metro app was opened previously and then closed when it windowed desktop move the application would show as active upon Display Fusions bar. I'm not sure if this is the OS or Display Fusion but its happening.
This is currently on our list to fix. At the moment we can't detect when a Metro app is closed. They respond as if they're still running with every check we do (visibility, hit tests, etc). We'll hopefully get it sorted out though
