


If you disable save taskbar thumbnail previews, all taskbar thumbnail previews will load on the fly as opened instead of from a cache. However, the cache could sometimes become corrupted causing taskbar thumbnail previews to not display correctly. If you enable save taskbar thumbnail previews, all taskbar thumbnail previews will be saved to cache as opened to help them load faster next time.

When you hover over the icon or button on the taskbar of opened items, it will show an instant thumbnail preview of the opened windows or tabs for that item. How to Enable or Disable Save Taskbar Thumbnail Previews to Cache in Windows
