I'm on Fedora 20 with Gnome3 and I want to show the overview by simply pressing the super/windows key, like in Ubuntu. But it won't let me set it because nothing happens when I click on the shortcut to configure it and then press super. It only works if I press super + some other key.
I also tried doing it from dconf > org > gnome > shell > keybindings > toggle overview:
['<Super>']. Doesn't work.