Re-Enable Window Grouping in GNOME Alt-Tab

Help! GNOME stopped grouping my open windows!
- criztovyl, II., 2016

TL;DR at end of page.
You must have disabled the Alternatetab shell extension but you wouldn't be here if you havn't already disabled it: It's task is to stop window grouping.

Symptoms

If you press Alt-Tab your open windows aren't grouped while they're still grouped when using Super-Alt. (The Super-key is also known as the Meta-key or the Windows-key.)

If you have the same problem I had, check your dconf, there should be Tab in /org/gnome/desktop/wm/keybindings/switch-windows.

This is what causes the problem because there shouldn't be anything. If you looked attentive you may found out that the default value here is empty. Couldn't imagine any solution, can't you? :D

Don't know what's dconf? Not soo important, the only thing you should do is to check the key within your dconf editor. Launch it by searching "dconf" in your overview or by pressing Alt-F2 and entering dconf-editor. Then follow the path mentioned above in the left-hand tree :)
You also could use the dconf command.
Anyway:

Now bring grouping back!

Reset the dconf value of "/org/gnome/desktop/wm/keybindings/switch-windows" to "" (None), below the simplest way.

$ dconf reset /org/gnome/desktop/wm/keybindings/switch-windows

 

Happy Alt-Tab-ing :)

Further information*

dconf - Alternatetab shell extension - GNOME tweak tool

TL;DR

• Alt-Tab does not group windows
• Alternatetab extensions is disabled
• Super-Tab works as expected
• Solution: execute dconf reset /org/gnome/desktop/wm/keybindings/switch-windows in terminal
  or reset dconf "/org/gnome/desktop/wm/keybindings/switch-windows" to "" (None) manually.

* informations... still chuckling.
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