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Ideally I would like a way of easily toggling it so that a Terminal window (or something of the sort) appears over the top of everything when I press a certain keyboard shortcut and then disappears again when the keyboard shortcut is pressed again (or another keyboard shortcut), but I would like it so that it stays on top of everything while another window is selected. Is there a way to get something like this? Preferably it would be a GNOME Shell extension. I am running Ubuntu GNOME 15.10 with GNOME 3.18.