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Firefox Quantum: Developer Edition

Get the latest features, fast performance, and the development tools you need to build for the open web.

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Developer resources

MDN

The best resource for the Open Web.

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Firefox DevTools

Edit and debug HTML, CSS, and JavaScript.

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WebAssembly

Use the .wasm format as a compiler target.

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Cross-browser testing

Easily test your site on every browser and operating system.

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Events to check out

Fresh from our blog

Fresh from our blog

  • New in Firefox 58: Developer Edition

    Dive into the changes coming in Firefox 58, currently available to preview in Firefox Developer Edition. Highlights include more control for CSS authors, an even better Debugger, added support for WebVR and FLAC, WebExtension API additions, and more.

    Read more

  • Comparing Browser Page Load Time: An Introduction to Methodology

    On blog.mozilla.org, we shared results of a speed comparison study to show how fast Firefox Quantum with Tracking Protection enabled is compared to other browsers. In this companion post, we share some insights into the methodology behind these page load time comparison studies and benchmarks. Our study focused on news web sites, which tend to come with an abundance of trackers, and uses the Navigation Timing API as a data source.

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  • A super-stable WebVR user experience thanks to Firefox Quantum

    The Quantum release incorporates major optimizations from Quantum Flow, an holistic effort to modernize and improve the foundations of the Firefox web engine by identifying and removing the main sources of jank without rewriting everything from scratch. Quantum Flow has had an important and noticeable effect on WebVR stability and performance, as Salva demonstrates in this article.

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