If I draw the same image several times on a context via drawImage(image, ...), only the first image is drawn to the context. The others are transparent or not available, don't know. It seems that the image is cleared after the first draw operation. This bug appears with this patch http://trac.webkit.org/changeset/37612. Only cairo seems to be affected. Qt has no problems with it. Could not test Cg yet.
Created attachment 24527 [details] Patch
Comment on attachment 24527 [details] Patch Needs a changelog. r=me
Fixed in r37740.