I tried doing it by
Keyboard > Custom Shortcuts > +, where I can enter the Name and Command just fine, but I can't seem to understand how to assign a keyboard shortcut to it. It just says Disabled.
I read the line which says
To edit a shortcut, click the row and hold down the new keys or press Backspace to clear, but when I click on the row, I just get this:
Nothing happens if I press any key combination. It closes only after I click Apply, and then also stays at