My main Xfce 4.6 panel developed a strange problem the other day. The thin line that represents its location while hidden at the bottom of the screen did not show up all the way across the screen. I had it set as full width, but the line did not extend to the right edge with the rest of the panel, and it failed to cover the workspace switcher, the clock, the notification area and the exit button, in that order from left to right. So the only way that one could get the panel to pop up and appear was to move the mouse pointer anywhere to the left of that group of items.
However, the panel stopped doing that when I started up my computer yesterday, and the active line now extends all the way across the screen again.
It remains very disturbing to see that sort of behavior, since it clearly indicates a failure of the programming to protect its product correctly.
Has anyone else experienced this? Does anyone have any insight into the cause?