In Windows 10 however, the live thumbnail preview is activated by the 'Peek' feature. But I still see thumbnails of my applications when I hover over them on the taskbar How to enable or disable Taskbar Thumbnail Preview in Can't turn off taskbar thumbnail previews in Windows 10 I've unchecked Enable Peek under Performance Options Visual Effects. This visual effect can be turned on or off. 1] Turn off Taskbar Thumbnails using System Advanced settings Taskbar Thumbnail Previews is a peeking feature that is a kind of visual effect on Windows.
