Came to computer, screen was locked, and orange glow (as though I had dragged a window to far left of screen, and it was showing me a preview of where it would snap to) was over left half of screen before I even logged back in, and I was on a clean desktop, with no windows open. It would not go away, and even after I unlocked screen, and it remained on desktop, and even in Expo view (covered whole left side of expo view - two desktops). Finally disappeared after second screen shot.
You are likely to be experiencing this bug that I recently reported: Bug #875557: Compiz grid plugin golden box appears after workspace switcher use. If so, please mark it as affecting you.
That looks like what happens when you drag a window all the way to the left to resize it in the screen grid.
Perhaps you could try settings in the Grid option in CompizConfig Settings Manager?
If you don't have it installed, do:
sudo apt-get install compizconfig-settings-manager
Start it up by running:
ccsm
Navigate to Window Management -> Grid.
You could either disable Grid entirely by unchecking the box on the left side,
Or you might try going to the "Appearance" tab and unchecking "Draw Indicator":
I'm not sure if that will work, but it might give you a workaround...
Hope it helps!
