Go to https://extensions.gnome.org/ and install from there.
Make sure you have xrandr installed.
Use gnome tweak tool to see whether the extension is really there and enabled.
Use looking glass to see more details (ALT+F2 lg)
Go to https://extensions.gnome.org/ and install from there.
Make sure you have xrandr installed.
Use gnome tweak tool to see whether the extension is really there and enabled.
Use looking glass to see more details (ALT+F2 lg)