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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

  • Thermostats, Locks and Extension Add-ons – WebThings Gateway 0.10

    Today we are releasing WebThings Gateway 0.10. This new release comes with support for thermostats and smart locks, as well as an updated add-ons system including extension add-ons, which enable developers to extend the gateway user interface. We’ve also added localisation settings so that you can choose your country, language, time zone and unit preferences.

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  • Upcoming notification permission changes in Firefox 72

    Earlier this year we decided to reduce the amount of unsolicited notification permission prompts people receive as they move around the web using the Firefox browser. This is an intrinsic part of Mozilla’s commitment to putting people first when they are online. In preparation, we ran a series of studies and experiments to understand how to improve the user experience and reduce annoyance. Now we’re making some changes to the workflow for how sites ask users for permission to send them notifications.

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  • Announcing the Bytecode Alliance: Building a secure by default, composable future for WebAssembly

    Lin Clark introduces the Bytecode Alliance, and uses Code Cartoon illustrations to share their vision of a WebAssembly ecosystem that is secure by default, fixing cracks in today’s software foundations. Based on advances in the emerging WebAssembly community, founding members of the Alliance – Mozilla, Fastly, Intel, and Red Hat – believe we can make this vision real. And we invite others to join the collaboration.

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Projects we love

A new layout system for the Web.

See grids in action

Mozilla’s next-generation web engine.

Get involved

A systems programming language that is fast and safe.

Check out Rust

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

Learn more

Build exciting virtual reality Web pages using HTML.

Start building