When I hover my mouse cursor over a running application's button in the taskbar, small windows appear showing the contents of the open program. How can I disable that? I find it quite annoying.
In Windows 8 or Windows 8.1 hit the Win+W keys (for search) and type in visual effects hit Enter and in the Performance Options window uncheck the option Animations in the Taskbar. I think this will do the trick.
On Windows 8.1 you can get rid of it with these settings:
Windows Registry Editor Version 5.00 [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Taskband] "NumThumbnails"=dword:00000000 [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced] "ExtendedUIHoverTime"=dword:41fffffe
Import them and restart Explorer. See here.
A few options (I've only tested option 4):
Option 1: (I haven't tested this one)
Click on Start button and type RegEdit in Instant Search text box, then hit Enter.
In the Registry Editor, navigate to the following registry key:
Note: If Explorer registry sub-key does not exist, then right click on Policies and click New -> Key and name it as “Explorer”.
In the right pane, right click and select New -> DWORD (32-bit) Value.
TaskbarNoThumbnail as the name for the new registry value
Double click on
TaskbarNoThumbnail to modify its value data.
Type 1 and click on OK.
Restart computer if needed.
To re-enable Taskbar thumbnails again, just right click on TaskbarNoThumbnail and click Delete to remove the whole registry key, or set TaskbarNoThumbnail value data to 0.
Option 2 and 3:
In the Hovering section, check the box 'nothing'
Install Taskbar Thumbnails Tuner - According to one person who commented on this page (jonesy), it works in Windows 8.1, but I haven't tested.
At the bottom, check the 'Disable thumbnails' box
Option 4: (I've tested this one)
Do what it shows in the first example, but instead of unchecking "Animations in the Taskbar"; uncheck "Enable Peek" instead.
This works for me in Windows 8.1