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I recently did a fresh installation of Ubuntu 13.10; but there is something bothering me, which I don't quite understand.
When I first tried to toggle the keyboard language(I usually switch between Persian and English) using the good old "Alt+Shift" shortcut it didn't work. Then, I went and checked the Keyboard shortcut settings and found out that it had been set to "Super+Space"(which BTW didn't work either). So I tried to change it back to "Alt+Shift" but it just doesn't work; when I press "Alt+Shift" to set it up as the toggle-language shortcut, the box automatically resets itself to its previous value(without any errors whatsoever). As far as I've checked I couldn't find any thing obvious corresponding to the shortcut "Alt+Shift" either.
I've currently set up the shortcut as "Ctrl+Space"; so I can toggle the language. My question is why I cannot set it up to just "Alt+Shift"?