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Joined March 2013
What should we ship in 2027? Rank your favourite features & create your wishlist: interop-rank.fxdx.dev/
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JPEG XL vs AVIF for web use-cases. @jaffathecake benchmarked both: AVIF produces smaller lossy files for photos, screenshots, and transparency, while JPEG XL wins at lossless. His default is AVIF 4:4:4 at high effort. #image #performance jakearchibald.com/2026/jpeg-…
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Firefox 158 landed today! For web devs: 🎉 JPEG XL support, including full progressive rendering. 🎉 'navigate' on notifications, so they can go to a URL without firing events. 🎉 WebGPU's float32-blendable 🎉 WebGL's EXT_polygon_offset_clamp And more! developer.mozilla.org/en-US/…
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What do you want us to work on in 2027? Here's a web app where you can rank the Interop proposals you care about, giving us data we can use to prioritise feature development. interop-rank.fxdx.dev/
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Firefox 157 has landed, and includes a couple of useful CSS features: 🎉 at-rule() in @supports - limit rules to browsers that support a given at-rule. 🎉 overscroll-behavior: chain - allow chained scrolling without overscroll effects. …And more! developer.mozilla.org/en-US/…
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When and how CSS custom property values are calculated might not be what you expect, and it has a big impact on your styles…
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Major versions of Firefox now land every two weeks, so Firefox 155 dropped today with web platform features including: 🎉 Fully typed CSS attr() 🎉 CSS progress() 🎉 Promise.allKeyed() and allSettledKeyed() 🎉 Lots of new WebTransport stuff …And more! developer.mozilla.org/en-US/…
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CSS text-box is newly baseline, and it's solves a common text layout issue. Here's how it works: instagram.com/reel/DcORXuGFN…
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Firefox 154 landed today, and brings with it some great web platform features: 🎉 CSS text-box 🎉 CSS sibling-index() and sibling-count() 🎉 JS Iterator methods like chunks, window, includes, & join 🎉 HTTP No-Vary-Search …And more! developer.mozilla.org/en-US/…
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JS promise integration for WebAssembly landed in Firefox 153, making it easier to work with asynchronous calls from Wasm. Here's how it works:
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JS text imports landed in Firefox 153, making it the first browser to support this feature. Here's how it works:
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Notification actions landed in Firefox 152, allowing you to add quick action buttons to your notifications. Here's how they work:
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CSS field-sizing is newly baseline, meaning you can make various form fields size to their contents, without needing JavaScript.
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Firefox 152 landed today, and includes web platform features like: 🎉 CSS field-sizing 🎉 Notification actions 🎉 unadjustedMovement pointer locks 🎉 getAnimations() pseudoElement option …and more! developer.mozilla.org/en-US/…
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The Web Serial API landed in Firefox 151, allowing you to connect directly to microcontrollers, dev boards, 3D printers, power meters, and other serial-connected hardware from the web. Here's how it works:
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MDN Web Docs retweeted
Replying to @MozDevNet
@MozDevNet, this is a blessing to JavaScript, I just finished with it. developer.mozilla.org/en-US/… The Intl namespace and its objects are wonderful...
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MDN Web Docs retweeted
➕ Meet abs() in CSS The abs() function returns the absolute value of a calculation, keeping numbers, lengths, or percentages always positive. Useful for safer layouts and predictable visuals. Learn more here ↓ developer.mozilla.org/en-US/…
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MDN Web Docs retweeted
Meet Promise.try() ✨ A new static method that wraps any callback in a Promise - handling both sync and async execution uniformly. Start experimenting now 👇 developer.mozilla.org/en-US/…
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@\scope入ったの熱い caniuse.com/css-cascade-scop…
🦊 Firefox 146 is out! What's new: • Inspector: auto-hides unused CSS custom properties • contrast-color() + text-decoration-inset support • scope enabled by default • WeakMap/WeakSet now accept Symbol keys • WebDriver BiDi upgrades Release notes 👇 developer.mozilla.org/en-US/…
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