Avoid Alt+Tab grouping same application

• Open dconf-editor
• Go to org/gnome/desktop/wm/keybindings
• Move the value '<Alt>Tab' from switch-applications to switch-windows
• Optionally move '<Shift><Alt>Tab' from switch-applications-backward to switch-windows-backward
• If you want switch-windows to work across desktops, not just in the current desktop, you can also uncheck org/gnome/shell/window-switcher/current-workspace-only
• Close dconf-editor
• If using X11, press <Alt>F2, then type r to restart Gnome.

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