I just had to use a system backup from last month after Windows 11 died and am trying to get everything back to where it should be. Today I found that the DisplayFusion taskbar is showing over vlc fullscreen when the focus shifts to another app. "Show taskbar in front of fullscreen applications when they lose focus" is NOT checked. Somehow the monitor numbers swapped, could that be the cause?

Thank you for your response. However, after going through a long tedious set of steps I found on the web that was supposed to restore the number 1 to my primary display, which ultimately failed, I now have an earlier version of my graphics drivers that Intel's Driver & Support Assistant nonetheless says is up-to-date, and the problem seems to have gone away. Don't worry, though, as I will never learn my lesson and will keep trying to customize and optimize my computer in ways that are sure to lead to new and exciting problems for you to solve!