Jake Archibald

@jaffathecake
7.8K Followers
333 Following
1.3K Posts
Developer of sorts at Firefox, but this is my personal account. No thought goes unpublished. He/him.
GitHubhttps://github.com/jakearchibald
Jake Archibald23h ago
Hey! Presents1d ago

@jaffathecake has been producing short-form video on web platform stuff recently, and the videos are assembled, edited, and encoding entirely in the browser. In his session at All Day Hey! 2026, he'll dive into the new shiny features that make this possible.

Schedule and tickets: https://heypresents.com/conferences/2026/schedule

Jake Archibald1d ago
Firefox for Web Developers1d ago
hasUAVisualTransition landed in Firefox 149, making it available across all major engines. As well as having a very catchy name, it lets you avoid doubling up on page transitions. Here's how it works:
Jake Archibald1d ago
Folks who are interested in popover=hint: have a play with https://random-stuff.jakearchibald.com/popover-hint/ and tell me anything that doesn't make sense. Or watch this:
Jake Archibald1d ago
Firefox for Web Developers1d ago
The CloseWatcher API landed in Firefox 149, making it easy to listen for platform-specific 'dismiss' signals. Here's how it works:
Jake Archibald2d ago

MacOS: I see you've set Finder to appear on 'all desktops'

me: yes

MacOS: So when you cmd-tab to Finder, which desktop should I switch to?

me: well you shouldn't because…

MacOS: So I can switch to a random desktop? YAY!

Jake Archibald2d ago

MacOS: When I restart, would you like me to re-open all these apps?

me: no

MacOS: hmm well that's a shame because I am going to do that.

me: ok

MacOS: Should I open them all maximised on the same desktop?

me: no

MacOS: hmm well…

Jake Archibald2d ago
Show threadFirefox for Web Developers2d ago
In terms of popover=hint, I dug into it when scripting a video, and… I can't make sense of the behaviour at all. Here's my investigation so far if you want to follow along: https://github.com/whatwg/html/issues/12304 & https://github.com/whatwg/html/issues/12305
Jake Archibald2d ago
Firefox for Web Developers2d ago

Firefox 149 is out now, and adds bunch of new web platform features, such as:

🎉 The CloseWatcher API
🎉 popover=hint (although I'm concerned about the spec'd behaviour)
🎉 hasUAVisualTransition on PopStateEvent
🎉 font-family: math
🎉 The CSP reporting API

And more!

https://developer.mozilla.org/en-US/docs/Mozilla/Firefox/Releases/149

Firefox 149 release notes for developers (Stable) - Mozilla | MDN

This article provides information about the changes in Firefox 149 that affect developers. Firefox 149 was released on March 24, 2026.

MDN Web Docs
Jake Archibald3d ago
Firefox for Web Developers3d ago
There are many browsers, but only three widely-used engines. We maintain one of those engines - Gecko. Here's why we feel that browser engine diversity is essential for the future of the web https://blog.mozilla.org/netpolicy/2026/03/23/competition-innovation-and-the-future-of-the-web/
Competition, Innovation, and the Future of the Web – Why Independent Browser Engines Matter – Open Policy & Advocacy

Gecko matters because it ensures there’s an independent voice shaping how the internet evolves. Without Gecko, the landscape would be dominated by Apple and Google alone. Is that really the ...

Open Policy & Advocacy
Jake ArchibaldMar 19

Another customisable <select> demo to add to the pile. I had a lot of fun with anchor position, anchor containers, scroll containers, calc-size etc etc https://random-stuff.jakearchibald.com/fancy-select/

Chrome only… for now, but it falls back nicely.

Fancy Select