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ICC V4 and PNG Specification broken in Firefox

So, first off, Firefox is my favorite browser. I love it a lot. I'm also a pretty big supporter of Free and Open-Source Software.

With that said, I was wondering when and if Firefox will fully support ICC V4 profiles and the PNG specification.

I noticed that ICC V4 is not enabled by default, but even after setting gfx.color_management.enablev4 to true and setting gfx.color_management.mode to 1, ICC V4 is still not working properly.

You can test this yourself here: https://littlecms.com/blog/2020/09/09/browser-check/

Also, I noticed that PNG images of large sizes won't display at all in Firefox, resulting in a broken image icon.

You can test this yourself here: https://www.jwz.org/blog/2018/07/png-antics/

These seem to work at least passably well in other browsers, but I don't want to use other browsers! Does anyone know if Mozilla will fix these sometime? I do know that Little CMS is open-source under the permissive MIT license, so maybe Firefox could use that to fix the ICC V4 problem, if that could help. I don't know if using the latest version of libpng will help the other problem, but I know it is under a rather permissive BSD-style license.

I'm using Firefox 90.0.2 in case anyone is wondering.

So, first off, Firefox is my favorite browser. I love it a lot. I'm also a pretty big supporter of Free and Open-Source Software. With that said, I was wondering when and if Firefox will fully support ICC V4 profiles and the PNG specification. I noticed that ICC V4 is not enabled by default, but even after setting '''gfx.color_management.enablev4''' to '''true''' and setting '''gfx.color_management.mode''' to '''1''', ICC V4 is still not working properly. You can test this yourself here: https://littlecms.com/blog/2020/09/09/browser-check/ Also, I noticed that PNG images of large sizes won't display at all in Firefox, resulting in a broken image icon. You can test this yourself here: https://www.jwz.org/blog/2018/07/png-antics/ These seem to work at least passably well in other browsers, but I don't want to use other browsers! Does anyone know if Mozilla will fix these sometime? I do know that Little CMS is open-source under the permissive MIT license, so maybe Firefox could use that to fix the ICC V4 problem, if that could help. I don't know if using the latest version of libpng will help the other problem, but I know it is under a rather permissive BSD-style license. I'm using Firefox 90.0.2 in case anyone is wondering.

Modified by RodentCheese

All Replies (5)

This is because Firefox does not actually support ICC v.4 although it does have a user preference to pretend that it is supported (so for example the adapted primaries and whitepoint are treated as unadapted).

See https://bugzilla.mozilla.org/show_bug.cgi?id=488800

Are you possibly using a color profile for your monitor that is blocked on Mac by the sandbox?

  • bug 1524694 - [Mac] Fix gfx.color_management.display_profile for arbitrary profile paths [--]

So, apparently qcms is the culprit behind why Firefox has an issue with ICC V4. Could Little CMS fix that? Also, I only have one color profile for my display, which is the one it came with. I never touched the color settings of the monitor.

Large PNG images are still not being rendered in any case.

Is "large" means that width/height is bigger than 32000 px?

Yep! The image I linked to is 111972 px wide. The image is supposed to be a debugging output histogram that shows where a certain program found silence in an MP3 file and removed them. The image is ludicrously huge because the MP3 was over 6 hours long. The image displays just fine in Opera, yet doesn't show up at all in Firefox.