Anthony Frehner
@frehner.me
Web, standards, tooling, sports, video games. https://frehner.me
Working @Shopify, on Polaris (web components)
Working @Shopify, on Polaris (web components)
Pinned
Anthony Frehner
@frehner.me
· Sep 21
Finally got around to writing a post detailing this work a bit more;
CSSWG resolution
CSS spec update
WPT update
Two WebKit PRs.
And a blog post. Whew!
frehner.me/blog/fixing-...
CSSWG resolution
CSS spec update
WPT update
Two WebKit PRs.
And a blog post. Whew!
frehner.me/blog/fixing-...
A small write up on some of the additional things that we/I feel empowered to do with a component library now that we’re using web components and shadow dom
frehner.me/blog/web-com...
frehner.me/blog/web-com...
More Shadow DOM uses in component libraries
Using web components with shadow DOM for a component library helps prevent misuse, but also enables a myriad of other benefits, such as contextual design and origin trial experimentation.
frehner.me
November 28, 2025 at 4:42 PM
A small write up on some of the additional things that we/I feel empowered to do with a component library now that we’re using web components and shadow dom
frehner.me/blog/web-com...
frehner.me/blog/web-com...
Interesting learning about tc39’s decorators proposal & metadata extension:
If you subclass a class, the metadata object for the subclass is different than the parent class’ metadata, BUT, the subclass’ prototype gets set to the parent’s metadata.
1/2
If you subclass a class, the metadata object for the subclass is different than the parent class’ metadata, BUT, the subclass’ prototype gets set to the parent’s metadata.
1/2
November 24, 2025 at 11:18 PM
Interesting learning about tc39’s decorators proposal & metadata extension:
If you subclass a class, the metadata object for the subclass is different than the parent class’ metadata, BUT, the subclass’ prototype gets set to the parent’s metadata.
1/2
If you subclass a class, the metadata object for the subclass is different than the parent class’ metadata, BUT, the subclass’ prototype gets set to the parent’s metadata.
1/2
Reposted by Anthony Frehner
📣 Hear hear! The biggest savings on the Practical Accessibility course start *today*—for a limited time only.
Starting today, you can get the course for 30% off — that's $279 instead of $399. The discounted price excludes sales tax that may be applied depending on where you are buying from.
Starting today, you can get the course for 30% off — that's $279 instead of $399. The discounted price excludes sales tax that may be applied depending on where you are buying from.
The Practical Accessibility Course
A get-right-down-to-it online course for Web designers and developers who want to start creating more accessible Web user interfaces and digital products today
practical-accessibility.today
November 20, 2025 at 2:58 PM
📣 Hear hear! The biggest savings on the Practical Accessibility course start *today*—for a limited time only.
Starting today, you can get the course for 30% off — that's $279 instead of $399. The discounted price excludes sales tax that may be applied depending on where you are buying from.
Starting today, you can get the course for 30% off — that's $279 instead of $399. The discounted price excludes sales tax that may be applied depending on where you are buying from.
The iPhone Mirroring feature is super interesting; they’ve done a good job of mapping keyboard/mouse interactions to a touch device, even things like using the mouse to drag and highlight and in some cases right clicking.
Yet browsers still see the device as pointer: coarse
Yet browsers still see the device as pointer: coarse
November 17, 2025 at 12:23 AM
The iPhone Mirroring feature is super interesting; they’ve done a good job of mapping keyboard/mouse interactions to a touch device, even things like using the mouse to drag and highlight and in some cases right clicking.
Yet browsers still see the device as pointer: coarse
Yet browsers still see the device as pointer: coarse
My first TPAC is over.
Thanks to everyone who let me hang out with and talk to them. Looking forward to doing it again!
Thanks to everyone doing so much work behind the scenes to make the web better.
Thanks to @yoav.ws and Shopify for making it so I could go.
Thanks to everyone who let me hang out with and talk to them. Looking forward to doing it again!
Thanks to everyone doing so much work behind the scenes to make the web better.
Thanks to @yoav.ws and Shopify for making it so I could go.
November 14, 2025 at 11:33 PM
My first TPAC is over.
Thanks to everyone who let me hang out with and talk to them. Looking forward to doing it again!
Thanks to everyone doing so much work behind the scenes to make the web better.
Thanks to @yoav.ws and Shopify for making it so I could go.
Thanks to everyone who let me hang out with and talk to them. Looking forward to doing it again!
Thanks to everyone doing so much work behind the scenes to make the web better.
Thanks to @yoav.ws and Shopify for making it so I could go.
Put a sticker on my laptop for the first time ever, thanks to @ntim.me giving me one personally.
Is this what it feels like to get a tattoo for the first time? Haha
Is this what it feels like to get a tattoo for the first time? Haha
November 14, 2025 at 12:40 AM
Put a sticker on my laptop for the first time ever, thanks to @ntim.me giving me one personally.
Is this what it feels like to get a tattoo for the first time? Haha
Is this what it feels like to get a tattoo for the first time? Haha
Reposted by Anthony Frehner
What'd I miss?
components know:
- user stuff
- device stuff
- app stuff
- design stuff
- what stuff is in them
- what stuff they're inside
- etc
It's amazing how much a component can know on the web, and I'm going to try and list it all out. Help me 🤓
#CSS
nerdy.dev/components-c...
components know:
- user stuff
- device stuff
- app stuff
- design stuff
- what stuff is in them
- what stuff they're inside
- etc
It's amazing how much a component can know on the web, and I'm going to try and list it all out. Help me 🤓
#CSS
nerdy.dev/components-c...
Web components know about the user, device, variables, layout and more · October 30, 2025
As Miriam Suzanne says "components know stuff," but like, how much stuff?
nerdy.dev
October 31, 2025 at 12:31 AM
What'd I miss?
components know:
- user stuff
- device stuff
- app stuff
- design stuff
- what stuff is in them
- what stuff they're inside
- etc
It's amazing how much a component can know on the web, and I'm going to try and list it all out. Help me 🤓
#CSS
nerdy.dev/components-c...
components know:
- user stuff
- device stuff
- app stuff
- design stuff
- what stuff is in them
- what stuff they're inside
- etc
It's amazing how much a component can know on the web, and I'm going to try and list it all out. Help me 🤓
#CSS
nerdy.dev/components-c...
Fun to see my work in the release notes!
Webkit: Release Notes for Safari Technology Preview 229
Webkit: Release Notes for Safari Technology Preview 229
Webkit: Release Notes for Safari Technology Preview 229
webkit.org
October 3, 2025 at 1:46 AM
Fun to see my work in the release notes!
Polaris (web components) are now stable. The component APIs are unified across the Shopify ecosystem. Lots of hard work and alignment in this; lots of great devs contributing.
🎉
www.shopify.com/partners/blo...
🎉
www.shopify.com/partners/blo...
Polaris Goes Stable - The Future of Shopify App Development is Here (2025) - Shopify
Polaris is now GA. Today marks a milestone moment for Shopify developers: Polaris is now stable and the default library for building experiences across the entire Shopify ecosystem.
www.shopify.com
October 1, 2025 at 4:18 PM
Polaris (web components) are now stable. The component APIs are unified across the Shopify ecosystem. Lots of hard work and alignment in this; lots of great devs contributing.
🎉
www.shopify.com/partners/blo...
🎉
www.shopify.com/partners/blo...
Holy shit this is amazing! I love WPT so it’s going to be very cool to read through this all.
A few years ago I started writing about evolving web standards and @rbyers.net suggested I should cover WPT: the web platform tests project that most people working with the web have a vague idea about that has evolved into an engine of interoperability. since then, I've been tracking people down
How a Shared Test Suite Fixed the Web’s Biggest Problems
The story of Web Platform Tests (WPT), the collaborative test suite that transformed the web from an inconsistent platform into a stable one.
thenewstack.io
September 30, 2025 at 10:45 PM
Holy shit this is amazing! I love WPT so it’s going to be very cool to read through this all.
Maybe I should actually try to understand the words in the spec?
Nawww I’ll just blindly fire from the hip. What could go wrong?
(Note to self, try to understand words in the spec next time)
Nawww I’ll just blindly fire from the hip. What could go wrong?
(Note to self, try to understand words in the spec next time)
September 29, 2025 at 10:59 PM
Maybe I should actually try to understand the words in the spec?
Nawww I’ll just blindly fire from the hip. What could go wrong?
(Note to self, try to understand words in the spec next time)
Nawww I’ll just blindly fire from the hip. What could go wrong?
(Note to self, try to understand words in the spec next time)
Reposted by Anthony Frehner
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?
September 29, 2025 at 12:12 PM
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?
Finally got around to writing a post detailing this work a bit more;
CSSWG resolution
CSS spec update
WPT update
Two WebKit PRs.
And a blog post. Whew!
frehner.me/blog/fixing-...
CSSWG resolution
CSS spec update
WPT update
Two WebKit PRs.
And a blog post. Whew!
frehner.me/blog/fixing-...
September 21, 2025 at 8:58 PM
Finally got around to writing a post detailing this work a bit more;
CSSWG resolution
CSS spec update
WPT update
Two WebKit PRs.
And a blog post. Whew!
frehner.me/blog/fixing-...
CSSWG resolution
CSS spec update
WPT update
Two WebKit PRs.
And a blog post. Whew!
frehner.me/blog/fixing-...
Many HRs just barely clear the wall. That implies that batters only put enough strength in to clear the wall, and no more
If we move the wall back further, batters would adjust and put more strength into it
Over time we could train batters to hit 600ft HRs by gradually moving the wall further back
If we move the wall back further, batters would adjust and put more strength into it
Over time we could train batters to hit 600ft HRs by gradually moving the wall further back
September 18, 2025 at 5:55 PM
Many HRs just barely clear the wall. That implies that batters only put enough strength in to clear the wall, and no more
If we move the wall back further, batters would adjust and put more strength into it
Over time we could train batters to hit 600ft HRs by gradually moving the wall further back
If we move the wall back further, batters would adjust and put more strength into it
Over time we could train batters to hit 600ft HRs by gradually moving the wall further back
Just got my third PR merged into WebKit. Yay!
Container queries and shadow dom will now work nicely together across all browsers.
Container queries and shadow dom will now work nicely together across all browsers.
September 16, 2025 at 4:23 PM
Just got my third PR merged into WebKit. Yay!
Container queries and shadow dom will now work nicely together across all browsers.
Container queries and shadow dom will now work nicely together across all browsers.
Reposted by Anthony Frehner
Safari 26 is here!!! Anchor Positioning, Scroll-driven animations, High Dynamic Range images, the new HTML element, the all-new Digital Credentials API, SVG icon support, WebGPU, WebKit in SwiftUI, every site can be a web app on iOS and iPadOS, and much more.
webkit.org/blog/17333/w...
webkit.org/blog/17333/w...
WebKit Features in Safari 26.0
We’re happy to share with you what’s arriving in Safari 26.0!
webkit.org
September 15, 2025 at 5:07 PM
Safari 26 is here!!! Anchor Positioning, Scroll-driven animations, High Dynamic Range images, the new HTML element, the all-new Digital Credentials API, SVG icon support, WebGPU, WebKit in SwiftUI, every site can be a web app on iOS and iPadOS, and much more.
webkit.org/blog/17333/w...
webkit.org/blog/17333/w...
Dang. Thought I was gonna be able to get a clean PR up to WebKit this weekend but the devil in my machine said no.
So close though
So close though
September 14, 2025 at 3:39 AM
Dang. Thought I was gonna be able to get a clean PR up to WebKit this weekend but the devil in my machine said no.
So close though
So close though
@lmfinney.bsky.social nice talk on signals, observables, etc
September 12, 2025 at 8:07 PM
@lmfinney.bsky.social nice talk on signals, observables, etc
@jakearchibald.com here’s a fun edge case for Firefox haha
(I’m not asking you to work on it, just thought it would be interesting for you since you have context on why I would be hitting this 😃)
bugzilla.mozilla.org/show_bug.cgi...
(I’m not asking you to work on it, just thought it would be interesting for you since you have context on why I would be hitting this 😃)
bugzilla.mozilla.org/show_bug.cgi...
1988232 - Calling .focus() on a Custom Element with delegatesFocus fails when host is display:contents
UNCONFIRMED (nobody) in Core - General. Last updated 2025-09-11.
bugzilla.mozilla.org
September 11, 2025 at 5:23 PM
@jakearchibald.com here’s a fun edge case for Firefox haha
(I’m not asking you to work on it, just thought it would be interesting for you since you have context on why I would be hitting this 😃)
bugzilla.mozilla.org/show_bug.cgi...
(I’m not asking you to work on it, just thought it would be interesting for you since you have context on why I would be hitting this 😃)
bugzilla.mozilla.org/show_bug.cgi...
I’ve been watching this proposal for a bit and it would be great to see it built into the platform. A near necessity for web components at times.
Okay, chat. Vote it up. #WebComponents github.com/web-platform...
Reference Target for Cross-Root ARIA · Issue #1011 · web-platform-tests/interop
Description There is a common footgun in web components where elements outside the shadow root (e.g. <label for="input">) are unable to reference elements inside the shadow root (e.g. <fancy-input>...
github.com
September 5, 2025 at 2:55 AM
I’ve been watching this proposal for a bit and it would be great to see it built into the platform. A near necessity for web components at times.
Reposted by Anthony Frehner
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...
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...
github.com
September 4, 2025 at 4:30 PM
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...
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...
Guess I’ll never know what the children were doing
August 29, 2025 at 8:16 PM
Guess I’ll never know what the children were doing
Hey, got my first contribution of code to openui merged today.
Yay 🎉
Yay 🎉
August 26, 2025 at 10:21 PM
Hey, got my first contribution of code to openui merged today.
Yay 🎉
Yay 🎉
Dang it’s kind of nice to be behind the curve on web components because all the hard issues have already been thought about and solved.
::part()? Yeah it’s there. In fact we’ll do you one better and also add exportparts
::part()? Yeah it’s there. In fact we’ll do you one better and also add exportparts
August 21, 2025 at 12:20 PM
Dang it’s kind of nice to be behind the curve on web components because all the hard issues have already been thought about and solved.
::part()? Yeah it’s there. In fact we’ll do you one better and also add exportparts
::part()? Yeah it’s there. In fact we’ll do you one better and also add exportparts
Oooh nice CSSWG resolved my question (container names in shadow roots are resolved against the flat tree)
Time to work on some WPTs and update Safari again
Maybe this time I try to update chromium too
Time to work on some WPTs and update Safari again
Maybe this time I try to update chromium too
August 20, 2025 at 12:33 PM
Oooh nice CSSWG resolved my question (container names in shadow roots are resolved against the flat tree)
Time to work on some WPTs and update Safari again
Maybe this time I try to update chromium too
Time to work on some WPTs and update Safari again
Maybe this time I try to update chromium too