Comment 139 for bug 1218322

@nrbrtx, Gnome 3.10 from Gnome PPA allows to switch with ctrl+shift, so no reason to blame Gnome here. The problem is in Ubuntu infrastructure in common (unity, gsd, ibus, etc.). My wild guess is that Unity now intercepts all modifier keys (not just Alt like it was before) and then when user presses any normal key it passes the keypress event to the application.