By default there is a slight delay when hovering your mouse over a Taskbar Thumbnail. Here is a registry hack that will allow you to speed it up.
Registry Hack
- Type regedit into the search box in the Start Menu and hit Enter.
- Navigate to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced and right-click to create a new DWORD 32 bit and name it ExtendedUIHoverTime.
- Now double-click on it and give it a Decimal value of “1″ click OK, close the Registry Editor, then logoff and log back back on for it to go into effect.
- When you come back, you’ll notice when you hover your mouse over any thumbnail of an open app/program on the Taskbar the preview pops up instantly without delay
To Slow it Down:
If for some reason you want to slow it down you can do that too. Just change the Decimal value to 1000 which is milliseconds. Then the delay will be longer. You can change the value to whatever you want for your needs.
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