More corruption, not only window borders. I've attached an image where part of a pop-up-context-menu in Thunderbird is not being drawn.
Another thing: when the corruption happens in the Gnome Panel, as in the image that I've already attached in #5, it's the actual desktop background that gets displayed instead of the Gnome Panel. In the example image of #5, it looks black, but choosing another background reveals that it's the background that's being displayed instead of the Gnome Panel.
More corruption, not only window borders. I've attached an image where part of a pop-up-context-menu in Thunderbird is not being drawn.
Another thing: when the corruption happens in the Gnome Panel, as in the image that I've already attached in #5, it's the actual desktop background that gets displayed instead of the Gnome Panel. In the example image of #5, it looks black, but choosing another background reveals that it's the background that's being displayed instead of the Gnome Panel.