I tried to AI code some in-browser video decoding stuff. It made a mess. So I learned the APIs somewhat properly, and did a much better job, but it was still messy. Then I found mediabunny.dev and it just worked. Yay!

Last week I posted about a secret config in Firefox that made view transitions easier to debug. Folks said we should make it less secret. So we did.

JavaScript top-level await is no longer considered 'baseline' due to a pretty big Safari bug caniuse.com/mdn-javascri... The module graph fails in cases where two modules import a third at the same time. Demo: random-stuff.jakearchibald.com/bug-repros/t... It's best to avoid the feature for now 😔

@mikehall314.bsky.social hmm kinda looks like the slide is introducing the panel

AV1 is crazy-good for encoding screencasts. 1:28 of video, higher-than-HD resolution, less than 2mb. bugzilla.mozilla.org/show_bug.cgi... There's not a lot of movement, but many codecs just don't handle that well.

Don't [...spread] or .split() your strings! Use Intl.Segmenter API. Available in every JS runtime

Match URLs with a powerful, standardized syntax using the URL Pattern API → goo.gle/47iTr3o Now part of Baseline, this API provides a built-in way to create URL pattern matchers that can be used against URLs or individual URL components.

📝 Importing vs fetching JSON JSON imports are now supported cross-browser, but when would you use them rather than fetch()? jakearchibald.com/2025/importi...

Aside from "it's the new W3C logo, with the text 'world wide web consortium' in a circle around the outside", what alt text would you use to describe this?

New in Firefox nightly (146.0a1 2025-10-19): large lists of unused CSS custom properties are collapsed by default. This not only reduces clutter, it also massively speeds up the rendering of the inspector panel in some cases.

c'mon bsky, support 60fps video!

We're currently working on devtools for view transitions in Firefox, but in the meantime, here's a little-known option that helps…

Love getting linked to a TikTok and you wanna unmute it but you gotta bring your machete to get down there.

📣 Firefox 144 is out! What's new for developers: 🧩 View Transition API for SPAs ⚙️ New Map/WeakMap methods (getOrInsert) 🧱 Element.moveBefore() 📱 ScreenOrientation.lock() 🕐 Built-in time picker for <input type="datetime-local"> (🧪exp.) Read more 👇 developer.mozilla.org/en-US/docs/...

With View Transitions now being Baseline Newly available, and the View Transition API consisting of various features, it can be confusing to know what is supported in which browser versions. To help with that, I created this VT Feature Explorer (powered by View Transitions) web.dev/blog/same-do...

I dug into progressive image rendering and found a bunch of common assumptions aren't quite true. ➡️ JPEG & WebP progressive-renders worse in Safari ➡️ AVIF _does_ support progressive ➡️ But JPEG XL in Safari doesn't ➡️ JPEG XL decodes much slower than AVIF ⬇️ and more jakearchibald.com/2025/present...

We've already had a great response to this. Thank you everyone who took the time to make a ranking - I know there's a lot of proposals. If you haven't, there's still time! bsky.app/profile/fire...

I am once again bewildered by the motives of people who knock on the door of an occupied public toilet.

Hello other parts of the world! If you'd like to tell us your preferences from a list of web features people are already describing as "a bit long", here's how: bsky.app/profile/fire...

This was… quite quickly thrown together, so hopefully everything works well! I'm really hoping it gives developers more of a voice in the process. Feel free to shout at me if anything doesn't look right. bsky.app/profile/fire...

There are… a lot of proposals, but you don't need to rank them all. Skim through the list, and find the few you really care about. This is an experiment, so we're also interested in feedback on the app itself, and things we can improve for next year.

As an experiment, we (the Firefox team) wanted to try a new way to get feedback on which Interop proposals matter most. So, here's a web app where you can rank the proposals you care about, giving us data we can use when reviewing which ones to champion. interop-rank.jakearchibald.com

Folks who want to see JPEG-XL supported in more browsers, what is it about the format that attracts you to its use on the web?

I'm actually quite impressed by Google's AI search, but hah it does this _a lot_.

There was a period during my time at Chrome where a well-resourced sub team did significant amounts of free work for Vercel. This included giving Rauch a talk at Chrome Dev Summit. I was asked to switch squoosh.app from Preact to Vercel, and was told I wasn't a team player for refusing. Mad.

What's next? Playing badminton with Skelator?

Web component folks: A common feature with request is to "inherit from a button". If that's something you want, which specific button behaviours is it you want to inherit? Why is putting a button in the shadow root not the answer?

SVGOMG has been updated to use SVGO 4! (thanks Adrien Crivelli!) This is the URL for SVGOMG. Unfortunately someone maintains a fork with ads, so, err, don't use that 😀 jakearchibald.github.io/svgomg/

Is it in the constitution that US podcasters have to pick between Alex Jones voice & Tina Belcher voice?

🧪 Thinking of using fetch() streams to track upload/download progress? @jakearchibald.com shares more, and how could limit future browser optimizations. ✅ Streams = Great for parallel processing ❌ Streams ≠ Reliable for measuring up/down % Read more 👇 jakearchibald.com/2025/fetch-...

The arbiter of good taste

New metal album just dropped

📝 Fetch streams are great, but contrary to popular belief, they're not good for measuring upload/downloading progress. ⬇️ Here's why, and how to avoid the gotchas ⬇️ jakearchibald.com/2025/fetch-s...

📝 Fetch streams are great, but contrary to popular belief, they're not good for measuring upload/downloading progress. ⬇️ Here's why, and how to avoid the gotchas ⬇️ jakearchibald.com/2025/fetch-s...

I'm in Liverpool this weekend. Chatted to a local old white bloke who spoke with pride about the city having the first mosque in the country, and the first chinatown. And… fuck, I needed to hear that kind of positivity.

📣 Web devs — we need your input! We're running a short survey (1–2 min) to understand interest in using ReadableStream as a request body in the Fetch API. Help us guide implementation priorities, especially around support & use cases. Fill it up! 👇 survey.alchemer.com/s3/8460326/...

I say this every year and always mean it: WOW, what a speaker (and MC!) lineup we have for @perfnow.nl conference this year! I can't wait to see all these folks on the stage! This is when #PerfNow ticket sales start to go bananas — and we always sell out — so lock in your ticket soon! perfnow.nl

?????

Interop 2026 is now open for proposals! This is your chance to tell browser-makers which well-defined, well-tested features you wish had better support across browsers. ⬇️ Here's how ⬇️ github.com/web-platform...

Hey folks! Are you interested in fetch upload streams? If so, what do you want to use them for?

📝 Making XML human-readable without XSLT. Turns out, JavaScript works pretty well! jakearchibald.com/2025/making-...

📝 Making XML human-readable without XSLT. Turns out, JavaScript works pretty well! jakearchibald.com/2025/making-...

Folks who use Firefox Developer Edition: What drew you to that version rather than Firefox Release/Beta/Nightly?

Here's a quick and efficient way to remove `autoplay` from videos if the user prefers reduced motion codepen.io/jaffathecake... `animationstart` is one of my favourite hacks for monitoring elements appearing in the DOM.

yeah no I'm alright thanks

Yay! It's the first Firefox release since I've joined the team, so let's take a look at some of the new developer-facing features in Firefox 142… 🧵

View Transitions are enabled by default in Firefox Nightly, so they're on their way to stable. Give it a test with your current transitions, and give me a shout if anything doesn't look right.

I'm going to be there (I'm not speaking, but come talk to me). The schedule looks great!

There's staging a house, then there's entirely faking it with AI slop, and this one is the latter www.rightmove.co.uk/properties/1...

Starting my new role on Monday. Could be anywhere.