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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

  • Progressive Web Games

    Web game developer Andrzej Mazur explores the concept of Progressive Web Games. He describes howe to use PWA features built with Web APIs for modern game development. He introduces the Enclave Phaser Template (EPT) — a free, open sourced mobile boilerplate for HTML5 games that provides many shortcuts for getting started.

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  • New in Firefox 61: Developer Edition

    The latest release — Firefox 61 Developer Edition — comes with a darker dark theme, more powerful and customizable developer tools, the new Accessibility Inspector, and numerous performance improvements like better CSS stylesheet parsing and improved time to first paint.

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  • Debugging Modern Web Applications

    The Firefox Dev Tools team released an upgrade to the debugger’s source map support. It lets you inspect the code that you actually wrote. Combined with the ongoing work to provide first-class JS framework support across all Firefox devtools, these advances boost productivity for web app developers working in frameworks like React, Angular, and Ember and with modern tools like Webpack, Babel, and PostCSS.

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Projects we love

A new layout system for the Web.

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Mozilla’s next-generation web engine.

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A systems programming language that is fast and safe.

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Powerful Web technologies that help push games to the new level.

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Build exciting virtual reality Web pages using HTML.

Start building