There are a few different bug filings for this problem. From reading through them, it may be related to nVidia, as the only reported video cards have been nVidia. I have an nVidia 8600 with the proprietary driver and a dual display setup, and I'm running 64 bit Ubuntu.
Switching between virtual desktops seems to get rid of the shadow easily.
There are a few different bug filings for this problem. From reading through them, it may be related to nVidia, as the only reported video cards have been nVidia. I have an nVidia 8600 with the proprietary driver and a dual display setup, and I'm running 64 bit Ubuntu.
Switching between virtual desktops seems to get rid of the shadow easily.