I have already tried adding the registry entry in HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced as ExtendedUIHoverTime with a value of 30000 seconds but it doesn't work. It still shows the Microsoft damned thumbnails, any idea?
7+ Taskbar Tweaker can disable taskbar thumbnails. It's very lightweight and supports a lot of other useful customizations.
I used this method:
In the right-hand pane, right-click and choose New – DWORD (32-bit) Value . Give it the name
NumThumbnails. You’ll create the 32-bit DWORD whether you have 32-bit or 64-bit Windows. By default, it should have a value of 0, which is what we want.
@anadrol's answer is correct and doesn't involve installing any potentially unwanted software. Here's a powershell answer:
New-ItemProperty HKCU:\Software\Microsoft\Windows\CurrentVersion\Explorer\Taskband -Name "NumThumbnails" -Value 0 -PropertyType "DWord"
Then restart explorer:
ps explorer | kill
Thumbnails will be replaced with a window list:
You need to edit the registry. Set NumThumbnails to 1 (0 doesn't work in Windows 10)
If NumThumbnails is set to 1, if more than one instance of a program is open, the taskbar thumbnails won't show up. Instead they appear stacked.
However, when a single instance of a program is running, the thumbnail still shows up.
Maybe the following will be useful for somebody - thumbnail preview will be replaced with list of windows in case that more than one instance has been opened. Please see examples below with Explorer windows tested on Windows 10 Enterprise 1903 (18362.239)