Mozilla plans to enable WebRender for all supported operating systems and devices in Firefox 92. WebRender is currently available on macOS (since Firefox 84) and most Linux distributions (since Firefox 91). With the release of Firefox 92, WebRender will also be enabled on Windows and Android devices.

WebRender is a GPU-based 2D rendering engine written in Rust and is used by Firefox, the research web browser Servo and many other GUI frameworks. webRender uses the OpenGL API internally.

WebRender renders pages faster and more smoothly, and Mozilla has invested a lot of time in the WebRender rendering engine. As early as Firefox 67, Mozilla started making the rendering engine available for testing on some devices, but even now Firefox is still not fully WebRender enabled.

Currently users can see if Firefox is using WebRender to render web pages by.

  1. load about:support in the Firefox address bar
  2. Scroll down to the “Graphics” section
  3. check that the Compositing value is set to WebRender

Tip: You can also press Ctrl-F on this page to search for WebRender.

If the device’s GPU supports it, WebRender can use hardware acceleration for rendering. If it is not supported at GPU level, it will be emulated using software. When Firefox users encounter rendering problems, their only option will be to switch WebRender to software rendering.

Firefox 92 is scheduled to be released on 7 September 2021, according to Mozilla’s development plan.