Quantum CSS, aka Stylo, aims to integrate Servo’s parallelized CSS style system written in Rust into Gecko.

Stylo is built with Firefox Nightly and is now ready for wider community testing. If you are using Firefox Nightly, you need to flip the pref layout.css.servo.enabled to true so as to use Stylo.

If you want to help test Stylo but haven’t yet installed Firefox Nightly, install it from nightly.mozilla.org and don’t hesitate to have a look at our community documentation about Nightly.

You can ask developers questions about Stylo in the #servo IRC channel (irc.mozilla.org/servo), if you find a bug please file it in our Bug tracker, Bugzilla. The component to file your bugs in is Core::CSS Parsing and Computation and start your summary field with Stylo: .

Here is a shortcut url to file bugs in this component:

New Stylo bug – Core::CSS Parsing and Computation

Stylo is making Firefox Nightly rendering of pages even faster and we are now working on chasing correctness and stability bugs so as to ship Stylo by default in Firefox 57, help us build this faster browser today, find and report bugs!

2017-09-06 update: