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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

  • 360° Images on the Web, the Easy Way

    One of the most popular uses for VR today is 360° images and video. These are easy to discover and share online, and you don’t need to learn any new interactions to explore the 360° experience. But building 360° views is not as easy as exploring them. In this post, Josh shows you how to easily build a 3D tour using A-Frame and Glitch.

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  • MDN Changelog for June 2018

    Our monthly changelog documents what happened in June to the code, data, and tools that support MDN Web Docs site. The team shipped 100+ HTML interactive examples in June. They additional shipped tweaks and fixes by merging 252 pull requests, including 32 pull requests from 26 new contributors. Finally, the team shipped Django 1.11 and laid the groundwork for a variety of performance enhancements that will roll out in July and beyond.

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  • Dark Theme Darkening: Better Theming for Firefox Quantum

    A team of computer science students from Michigan State University’s capstone program went to work on Firefox Quantum’s Theming API. Their goal: Expand upon the existing “lightweight” Theming API in Quantum to allow for more areas of customization. Themes had the ability to alter the appearance of the default toolbars, but did not have the ability to style menus, or customize auto-complete popups — till now. The team also worked on adding a more fluid transition when dynamic themes change, to allow for a smoother user experience.

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