sRGB PNGs handled with inappropriate colour correction

Binary package hint: firefox

firefox-3.5.3+nobinonly-0ubuntu6 on Karmic beta

Firefox is treating PNGs containing the 'sRGB' chunk as having a specific colour space different to the current colour space, and attempt to ‘correct’ it, resulting in colours that do not match other HTML, CSS and image colours on the same page.

This is a similar problem to that which occurs when a gAMA chunk is present and some past browsers have also had this behaviour, but it is generally considered undesirable: sRGB PNGs on the web should be rendered the same as unlabelled-colour-space PNGs.

To reproduce, create a small image with fully-blue colour, save it as a PNG from GIMP (which, unfortunately, adds an sRGB chunk to all saved PNGs; an issue has been filed upstream to request this is stopped) and load it into an HTML page with body bgcolor="#0000FF". An example test case can be found temporarily at http://www.doxdesk.com/file/blue.html

Expected result: completely blue page. Actual result: the image in the top-left is discoloured.

This issue does not occur in Firefox 3.5.3 on Windows or Slax (KDE3), or Shiretoko 3.5.3 on Jaunty, which is why I'm filing it here not upstream. However these other distros were tested in a VirtualBox, if that makes a difference. I'm not familiar with how colour spaces are managed under Ubuntu and Firefox in general, if they are managed at all, and whether EDID data could make a difference when running virtualised.