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[MDN Web Docs @MozDevNet]

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Press ⚙️ Settings on any compat table to choose which browsers and engines you see, and hide the ones you don't need.

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https://t.co/bIxzUu4WOe

[MDN Web Docs @MozDevNet]

@ChromiumDev @FirefoxWebDevs @MSEdgeDev Thanks, @ChromiumDev! We’re excited to help shape Modern Web Guidance and make sure it works across every browser 🙌

[Firefox for Web Developers @FirefoxWebDevs]

Scoped custom element registries are newly available in all major engines, meaning multiple implementations can use the same tag name without clashing. Here's how they work:

[Firefox for Web Developers @FirefoxWebDevs]

Scroll-driven animations are newly available in all major engines! Here's how they work:

[Firefox for Web Developers @FirefoxWebDevs]

JPEG XL is newly available in all major engines, but how does it stack up against other formats?

[Firefox for Web Developers @FirefoxWebDevs]

What should we ship in 2027? Rank your favourite features & create your wishlist: https://t.co/xDo2xRpTRQ

[Web Standards @webstandardsdev]

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

https://t.co/8LD0P7W2z4

[Firefox for Web Developers @FirefoxWebDevs]

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!

https://t.co/P2JhyGZHEO

[Firefox for Web Developers @FirefoxWebDevs]

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.

https://t.co/xDo2xRpTRQ

[Firefox for Web Developers @FirefoxWebDevs]

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! https://t.co/t3M1vyEYqB

[Firefox for Web Developers @FirefoxWebDevs]

When and how CSS custom property values are calculated might not be what you expect, and it has a big impact on your styles…

[Firefox for Web Developers @FirefoxWebDevs]

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!

https://t.co/zGtRtYX1uk

[Firefox for Web Developers @FirefoxWebDevs]

CSS text-box is newly baseline, and it's solves a common text layout issue. Here's how it works: https://t.co/1bb6hCSjAZ

[Firefox for Web Developers @FirefoxWebDevs]

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! https://t.co/4w76Li3X1B

[Firefox for Web Developers @FirefoxWebDevs]

JS promise integration for WebAssembly landed in Firefox 153, making it easier to work with asynchronous calls from Wasm. Here's how it works:

[Firefox for Web Developers @FirefoxWebDevs]

JS text imports landed in Firefox 153, making it the first browser to support this feature. Here's how it works:

[Firefox for Web Developers @FirefoxWebDevs]

Notification actions landed in Firefox 152, allowing you to add quick action buttons to your notifications. Here's how they work:

[Firefox for Web Developers @FirefoxWebDevs]

CSS field-sizing is newly baseline, meaning you can make various form fields size to their contents, without needing JavaScript.

[Firefox for Web Developers @FirefoxWebDevs]

Firefox 152 landed today, and includes web platform features like:

🎉 CSS field-sizing
🎉 Notification actions
🎉 unadjustedMovement pointer locks
🎉 getAnimations() pseudoElement option

…and more!

https://t.co/zVWp2byhYX

[MDN Web Docs @MozDevNet]

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