When going fullscreen in a VirtualBox VM in the second monitor with DualMonitor Taskbar, the taskbar stays on top of the VM window
I'm having this problem as well. The taskbar doesn't auto hide when some applications go to full screen. Virtualbox is the most inconvenient because the taskbar for the virtual machine is hidden behind the Dual Monitor taskbar. And even if you have the taskbar set to auto hide it still covers the 1-pixel high popup menu that's used to control the Virtualbox windows.
Other applications that this bug affects:
IrfanView image viewer in full screen
foobar2000 music jukebox with full-screen visualizations turned on
Many other full-screen programs I've tested work just fine, so I don't know why these ones break.
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