HTML5 video mostly requires USE=gstreamer to be enabled. Otherwise random erroring makes users sad. At the same time USE="gmp-autoupdate" is enabled by default, while it shouldn't be. I suggest changing defaults to USE="+gstreamer gmp-autoupdate" for more reasonable user experience.
Yep, we can default-enable gstreamer with the next version bumps (nov.3rd). gmp-autoupdate unfortunately is not even optional upstream, I've hacked in the ability to disable it. So to keep things as default-upstream-compliant as possible we're going to keep that one.
We have adjusted for 42.x in mozilla overlay will leave open until we push 42.0 final to tree.
did someone just forget to close this bug?
Yep, so we did. Also, gstreamer suppor has been dropped so this bug is now obsolete, but i'll set it RESO/FIXED anyhow