Comment 13 for bug 717114

apw may have this same bug, he adds some of his observations:

<apw> i'd say its improved, is less reproducible recently
<apw> bryceh, i assume you know what it looks like. i have it right now in a wndow where scrolling down one shows it, one more and its ok again and reversing through the same 3 lines seems the same
<apw> looking closly at it, the 'dammage' is actually a ghost of what was on that line before the scroll, about half the lines vertically have not been cleared