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Today I noticed that a lot of the keyboard shortcuts I regularly use on Ubuntu 16.04 LTS have stopped working. I can no longer switch between workspaces using Ctrl+Alt+arrowkey and I can no longer manipulate windows using Ctrl+Alt+numberkey and I also can't drag windows to the side of the screen to make them fill half of the screen.
I've checked the keyboard shortcuts for switching workspaces and they appear to all be still set correctly.
Does anyone have any ideas what might be causing this? Or has anyone ran into this issue before?