User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:42.0) Gecko/20100101 Firefox/42.0 Build ID: 20150831004018 Steps to reproduce: Visited https://steamlug.org/mumble in 43.0a1 with gfx.content.azure.backends set to skia Actual results: The Mumble list of users uses css opacity to make channels and subchannels less intense. However with the skia renderer, this is making the background darker as well. Expected results: Unlike Firefox with cairo, and Chromium, this appears incorrect.

Put together an offline reproduction of that behaviour

Tentatively hanging this off bug 1007702 as well in case it's not Linux specific.

Upstream bug report with proposed fix: https://codereview.chromium.org/2097883002

This is a port of work I did in upstream Skia to fix this issue: https://skia.googlesource.com/skia/+/40254c2c2dc28a34f96294d5a1ad94a99b0be8a6 Also some tests needed to be fuzzed due to the slight differences in blending.

Pushed by lsalzman@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/ffd7f9c1bbf9 revise Skia row blits to preserve color when blended against itself. r=mchang