User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Firefox/38.0 Build ID: 20150525141253 Steps to reproduce: 1. Open https://gforge.inria.fr/project/stats/index.php?area=scmsvn&SPAN=3&start=1377993600&end=1438387200&group_id=136 2. Context menu → "View Image" (or "Save Image As..." and save the png image). Actual results: The image is blank, and the saved image shows only transparency. Expected results: One should get the displayed image. Not sure whether this is a related bug: https://bugzilla.mozilla.org/show_bug.cgi?id=749824 but this one is Windows only.