By default when I opened multiple windows of the same app like the Internet Explorer or Edge browser in Windows 8, hovering over its icon on the taskbar will show multiple previews. However, after I installed the Windows 10 Anniversary Update and used GPU Tweak app to optimize Game Booster mode, it only showed a list of the app’s name. How can I restore default taskbar Thumbnail preview on my Surface Pro 3 tablet?
How to enable Threshold of Taskbar thumbnail previews of opened items instead of showing thumbnail list in Windows 10
Note: You need to make changes with the Registry Editor so modify it carefully.
* Press Win + R from your keyboard, type regedit into Run box, and hit Enter. Or you can type regedit in Start menu and select it from results.
* Within the left pane of Registry Editor, navigate to the tree below:
* Select the Taskband key and go to its right side pane, double click/tap on the NumThumbnails string with DWORD type. If it doesn’t exist, right click the empty area, select New > DWORD (32-bit) Value, and set the name to NumThumbnails.
* Check the Decimal box under Base, change the value data to 1, and click OK button.
* Then sign out your current account and sign in again to enable taskbar thumbnail previews.
However, if the taskbar threshold is reached the limitation, the system will show a list afterwards for that item automatically. That depends on your screen resolution so you might re-configure the display. For example, the 1024×768 works with only 10 tabs fully while the 1920×1080 supports up to 16 tabs.