Hide Windows

Hide Windows is a simple application you can use to quickly toggle the visibility of your opened windows from a single spot. It's handy for creating a distraction-free zone by focusing on specific applications.

Doesn't require installation and has an outdated GUI

The program isn't wrapped in a portable package, so it can be stored anywhere on the disk or copied to an external storage device to directly deploy Hide Windows on any computer. Between the .exe and .bat file, make sure to double-click the .bat file to launch the tool.
It displays an outdated window with a minimalistic look that's initially empty. You can hide all windows currently opened from the Actions menu (this will list the title bars in the empty area), then display them again from this panel. The apps become hidden from both the taskbar and systray.

Restore all windows or just preferred ones using hotkeys

You can either restore all windows at the same time or select an entry from the list to restore only the corresponding panel. In addition, you can ask the application to run in the background, as well as re-register keyboard shortcuts from the File menu.
The application can be sent to run in the background as well as brought back to the screen using Ctrl + Alt + P. Also, you can press Win + F4 to hide the current window, Win + H to hide all windows, Ctrl + Alt + S to show all hidden windows, Ctrl + Alt + F1 to show only the first hidden window, Ctrl + Alt + F2 for the second, and Ctrl + Alt + F3 for the third.

Old, yet functional tool for controlling window visibility

All things considered, Hide Windows could have been a practical utility for giving you more control over the visibility of opened windows using hotkeys. Unfortunately, the application hasn't received updates for a long time; its interface needs more work and the list of hotkeys isn't available in the main window. Even so, we haven't come across any compatibility issues on Windows 10.