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I've noticed some time ago that some of my shortcuts in Ubuntu 14.10. stopped working. I hoped that update to 15.04. will fix it but unfortunately, that was not the case. I have a problem only with few shortcuts, not all of them. For instance:
default shortcuts to move windows to left or right (CCtrl + Super + left/right). I've tried to do this with mouse by dragging window but it stoped working as well...
default shortcuts for managing workspaces (Ctrl + Alt + Arrow, Ctrl + shift + alt + arrow).
I've been googling this already but I didn't find any solution. It seems to be unity problem but I don't have any other ideas to fix it.