Comment 65 for bug 1189850

(In reply to comment #45)
> Only if that pixman time is inside firefox and not Xorg...

I am not familiar with this tool. How do I check this?

> Have gentoo also
> disabled server-side gradients in cairo?

Yes, part of changelog:

10 Sep 2010; Samuli Suominen <email address hidden>
+cairo-1.10.0-r2.ebuild, +files/cairo-1.10.0-buggy_gradients.patch:
Do not use server-side gradients. It hurts performance, and causes bad
rendering on at least nvidia. Bug 336696.

And this patch is still applied on top of cairo version I am running now. Though maintainers added option to disable it in the latest version in tree. It enabled by default though, so I tested this version also with disabled gradients. Should I check without it?