Attempting to build firefox from scratch, with the flags "--with-system-png" produces a configure error that the system libpng does not support APNG (animated PNG) files. It would appear from [1] that animated PNG support is a relatively standard extension to libpng which might need an updated libpng ebuild which applies the patches provided (subject to an "apng" use flag) [and of course the libpng USE flag documentation would need updating]. This would allow libpng support for animation across multiple browsers without taking up excess memory. 1, The web site "http://littlesvr.ca/apng/" for further discussion (and patches as well as test cases). Reproducible: Always Steps to Reproduce: 1. Try to configure firefox sources with "--with-system-png" Actual Results: Configure fails with: "--with-system-png won't work because the system's libpng doesn't have APNG support" Expected Results: Firefox, mozilla, opera, etc. should be allowed to use the system PNG library with animation support.
This bug is INVALID due to many reasons. Among other: - "Attempting to build firefox from scratch": firefox is in the tree and the ebuild (including specialized eclasses involved) is among the most complex in the tree - those "animated PNGs", whatever they really are, seem to work just fine in Firefox (at least the examples from that site do) As far as the bug mentioned on that page says, it supported in Gecko, but not really (or not at all) in other web engines (or other apps).
*** This bug has been marked as a duplicate of bug 183370 ***
