Comment 242 for bug 182038

In case you can't duplicate this problem by running the JS code I posted above, here is an animated GIF of the image resizing problem.

http://web.mit.edu/~luke_h/www/anim.gif

Actually I think this bug may cover three different issues, not two: wrong image offset calculations, easily spotted in this animation; the transparency problem, previously discussed; and also there seems to be a third problem with uninitialized memory with certain sizes of these "black box" cases. You can see some dim brown stripes that run down the black box in the first frame of this animation. If you stop the JS code running at that point and open another window, the pattern of lines changes, it's like the first row of the black box is pulling in data from some X shared memory, and that is copied all the way down. Dragging another window over the top of the black box causes trails to be left behind.

Ironically, on a "broken system", the above animated gif displays wrong too, it gets cropped into a narrow wide box near the top of the browser window, and as it animates, some window decoration junk gets inserted at the edges of the box along with content of the gif animation itself...