Recently I noticed that when I switched to another active application on my taskbar, Windows 10 didn’t show the application. Very annoying.. 🙁 The application (and the preview screen) showed while switching with alt-tab, but after releasing the application disappeared again!
I found the following solution :
Hover to the application that is having that problem on your taskbar.
With for the preview screen to pop up and slowly go to that screen. Now use your right mouse button to select and choose for maximize.
Voila! There it is again!