Firefox WebRender

WebRender is a major rewrite of the Firefox rendering architecture using the same kind of GPU-based acceleration techniques used by games.

To turn on WebRender, go to about:config, enable the gfx.webrender.all pref, and restart the browser. Note: doing so may cause pages to render incorrectly, your browser to crash, or other problems. Proceed with caution!

On Firefox 68.0.1 with Intel HD Graphics 4600 and GNOME/Wayland, I do notice a performance increase while panning on google maps (satellite view).

  • Increases in performance may or may not be imaginary.

We currently have WebRender enabled in Nightly for:

  • Recent Intel and AMD GPUs on Windows 10 desktops
  • Linux users on Intel integrated GPUs with Mesa 18.2 or newer with screens smaller than 4K

“in Nightly”… so I guess I was imagining the performance increases.

The placebo effect gets another case study. rotfl!

Nice didnt hear about this feature. I guess we have to wait a bit more for it.

I see I forgot to post the link lol…

Another big part of the Firefox base (re-)written in Mozilla’s open-source Rust language.

Despite having used little except Ruby (my fave), plain C and a smattering of bash-scripting, I gotta say, Rust seems to do the business despite being incredibly harsh to developers in its evaluation of code. But that strictness is exactly what seems to successfully circumvent several classes of coding bugs.

Worth a try.

Yes I never used Rust or C but from what I read it would be nice to rewrite the Linux kernel in Rust.
Some project is already underway but it’s a huge effort.

I stopped using Firefox years ago because of performance issues. It was around the same time they changed their search bar and partnered with yahoo. I’m happy to say that with Firefox Quantum performance is once again acceptable.

Rust is interesting, I’ve actually been researching it the last few days.

In the end, we aim to make it compelling for users to not write new GObject libraries in C, but rather to give them an “obvious” way to it in Rust.

This post from Nate Graham arrived in Planet KDE last Saturday: <>.

  • Yes, on X11 it seems to reduce Firefox’s CPU usage …

[HR][/HR]P.S.: I have an AMD GPU and, I’m using the X11 Modesetting DDX …

There are a number of cool concepts that should make Firefox Webrender a great setting.
I’ve been reading a few blogs about Webbrender for the past few days, and all say it’s great.
Be aware that although Webrender is enabled by default on Windows, it’s not on Linux as of today… So if you want Webrender, you have to enable it

One of the main ways that Webrender improves performance is to run graphics on the GPU instead of CPU. Of course that makes sense and it’s a great implementation if it works, and based on early results is running great on Linux.
It’s also supposed to work its magic on both Xorg and Wayland so no concerns there.

So, go ahead and enable it today is my recommendation.
Eventually, it will likely be a standard configuration but today you need to manually invoke it.


Seems to work fine here as well, tested on this machine with Mesa DRI Intel(R) HD Graphics P4000 (IVB GT2), tested on the dual AMD gpu laptop (firing up firefox with/withou DRI_PRIME=1) all looks good.

Works here too on Firefox 68.0.2 esr with Mesa DRI Intel(R) Haswell Mobile, 3.0 Mesa 18.3.2 and Gnome/Wayland.
CPU usage is about 30-50% when panning satellite view compared to webrender=off.
Artifacts/doesn’t work with DRI_PRIME=1 and OSS drivers on GeForce GTX 960m on “Optimus” laptop.