Jen Simmons
@jensimmons.bsky.social
Apple Evangelist on the Web Developer Experience team for Safari & Webkit. #PwME
Reposted by Jen Simmons
CSS grid lanes are arriving sooner than you think. @jensimmons.bsky.social says Safari Technology Preview has the finalized syntax, while Chrome and Firefox are close behind. Meanwhile, you can use @supports for progressive enhancement and a CSS or JS polyfill fallback.
webkit.org/blog/17758/w...
webkit.org/blog/17758/w...
February 5, 2026 at 12:11 PM
CSS grid lanes are arriving sooner than you think. @jensimmons.bsky.social says Safari Technology Preview has the finalized syntax, while Chrome and Firefox are close behind. Meanwhile, you can use @supports for progressive enhancement and a CSS or JS polyfill fallback.
webkit.org/blog/17758/w...
webkit.org/blog/17758/w...
Are you using CSS Grid? If you write CSS & code layouts on the web, and not using Grid — why not?!?
I see so many sites that still use only Flexbox for 100% of their layout. 0% Grid.
Why?
What would help?
I hear people say it’s hard. Is it? What’s hard?
What do you want to learn about CSS Grid?
I see so many sites that still use only Flexbox for 100% of their layout. 0% Grid.
Why?
What would help?
I hear people say it’s hard. Is it? What’s hard?
What do you want to learn about CSS Grid?
February 3, 2026 at 10:07 PM
Are you using CSS Grid? If you write CSS & code layouts on the web, and not using Grid — why not?!?
I see so many sites that still use only Flexbox for 100% of their layout. 0% Grid.
Why?
What would help?
I hear people say it’s hard. Is it? What’s hard?
What do you want to learn about CSS Grid?
I see so many sites that still use only Flexbox for 100% of their layout. 0% Grid.
Why?
What would help?
I hear people say it’s hard. Is it? What’s hard?
What do you want to learn about CSS Grid?
Reposted by Jen Simmons
When will CSS Grid Lanes arrive? How long until we can use it? from @jensimmons.bsky.social on the webkit blog
webkit.org/blog/17758/w...
webkit.org/blog/17758/w...
When will CSS Grid Lanes arrive? How long until we can use it?
Anytime an exciting new web technology starts to land in browsers, developers want to know “when in the world am I going to be able to use this?” Currently, the finalized syntax for Grid Lanes is avai...
webkit.org
February 3, 2026 at 12:49 PM
When will CSS Grid Lanes arrive? How long until we can use it? from @jensimmons.bsky.social on the webkit blog
webkit.org/blog/17758/w...
webkit.org/blog/17758/w...
It’s wild to me just how much wrong information there is out there (written by humans in the later half of 2025) about using CSS to create masonry layouts.
There is no property named `grid-lanes` (as in grid-lanes: repeat(4, 200px)). There is no `masonry-direction` property. Or `masonry` anything.
There is no property named `grid-lanes` (as in grid-lanes: repeat(4, 200px)). There is no `masonry-direction` property. Or `masonry` anything.
January 23, 2026 at 10:08 PM
It’s wild to me just how much wrong information there is out there (written by humans in the later half of 2025) about using CSS to create masonry layouts.
There is no property named `grid-lanes` (as in grid-lanes: repeat(4, 200px)). There is no `masonry-direction` property. Or `masonry` anything.
There is no property named `grid-lanes` (as in grid-lanes: repeat(4, 200px)). There is no `masonry-direction` property. Or `masonry` anything.
Reposted by Jen Simmons
Whoop! Updating my CodePen!
codepen.io/dutchcelt/fu...
codepen.io/dutchcelt/fu...
Layout toggle with Web Component Cards
Created a singular layout structure that can easily utilize CSS's three main layout tools: 1. CSS Multiple-Column Layout 2. CSS Grid Layout 3. CSS Flex...
codepen.io
January 23, 2026 at 2:06 PM
Whoop! Updating my CodePen!
codepen.io/dutchcelt/fu...
codepen.io/dutchcelt/fu...
Reposted by Jen Simmons
I’ve been using r/lh unit for typography related content. A perfect example of this is @jensimmons.bsky.social article on vertical rhythm.
Polishing your typography with line height units
Learn how to use line-height units when setting paragraph margins — creating vertical rhythm in your text.
webkit.org
January 22, 2026 at 6:34 PM
I’ve been using r/lh unit for typography related content. A perfect example of this is @jensimmons.bsky.social article on vertical rhythm.
Excited about CSS Grid Lanes? Wondering when you can start using it? We’ve got you covered.
Updates on browser implementations + strategies for progressive enhancement.
webkit.org/blog/17758/w...
Updates on browser implementations + strategies for progressive enhancement.
webkit.org/blog/17758/w...
When will CSS Grid Lanes arrive? How long until we can use it?
Anytime an exciting new web technology starts to land in browsers, developers want to know “when in the world am I going to be able to use this?” Currently, the finalized syntax for Grid Lanes is avai...
webkit.org
January 22, 2026 at 10:15 PM
Excited about CSS Grid Lanes? Wondering when you can start using it? We’ve got you covered.
Updates on browser implementations + strategies for progressive enhancement.
webkit.org/blog/17758/w...
Updates on browser implementations + strategies for progressive enhancement.
webkit.org/blog/17758/w...
Web designers/developers,
What are your biggest questions about CSS Grid Lanes?
What are your biggest questions about CSS Grid Lanes?
January 16, 2026 at 6:26 AM
Web designers/developers,
What are your biggest questions about CSS Grid Lanes?
What are your biggest questions about CSS Grid Lanes?
Are you excited about CSS Grid Lanes?
It can be tricky to fully understand how content order works in this layout. Safari Technology Preview 235 just landed a new Order Number tool in our Grid Inspector to quickly see what’s up. Especially helpful with `flow-tolerance`.
webkit.org/blog/17746/n...
It can be tricky to fully understand how content order works in this layout. Safari Technology Preview 235 just landed a new Order Number tool in our Grid Inspector to quickly see what’s up. Especially helpful with `flow-tolerance`.
webkit.org/blog/17746/n...
New Safari developer tools provide insight into CSS Grid Lanes
You might have heard recently that Safari Technology Preview 234 landed the final plan for supporting masonry-style layouts in CSS.
webkit.org
January 14, 2026 at 11:09 PM
Are you excited about CSS Grid Lanes?
It can be tricky to fully understand how content order works in this layout. Safari Technology Preview 235 just landed a new Order Number tool in our Grid Inspector to quickly see what’s up. Especially helpful with `flow-tolerance`.
webkit.org/blog/17746/n...
It can be tricky to fully understand how content order works in this layout. Safari Technology Preview 235 just landed a new Order Number tool in our Grid Inspector to quickly see what’s up. Especially helpful with `flow-tolerance`.
webkit.org/blog/17746/n...
Reposted by Jen Simmons
📝 Algorithmic hover states with contrast-color() - Taking some cool new features for a spin.
daverupert.com/2026/01/algo...
daverupert.com/2026/01/algo...
Algorithmic hover states with contrast-color()
Firefox 146 added support for contrast-color() joining Safari 26 in the First Implementor’s Club. For those unfamiliar, contrast-color(<color>) is a new CSS function that will take a <color> as input ...
daverupert.com
January 8, 2026 at 5:26 PM
📝 Algorithmic hover states with contrast-color() - Taking some cool new features for a spin.
daverupert.com/2026/01/algo...
daverupert.com/2026/01/algo...
Today the CSS Working Group resolved to rename the property that lets you adjust the tolerance of how content lays out in CSS Grid Lanes to `flow-tolerance`!
Just updated the article about it with the new name.
webkit.org/blog/17660/i...
Just updated the article about it with the new name.
webkit.org/blog/17660/i...
Introducing CSS Grid Lanes
It’s here, the future of masonry layouts on the web!
webkit.org
January 8, 2026 at 12:56 AM
Today the CSS Working Group resolved to rename the property that lets you adjust the tolerance of how content lays out in CSS Grid Lanes to `flow-tolerance`!
Just updated the article about it with the new name.
webkit.org/blog/17660/i...
Just updated the article about it with the new name.
webkit.org/blog/17660/i...
Reposted by Jen Simmons
Any Focus Area that still needs work is considered for Interop 2026, but it’s not included automatically.
Maybe some of these will be carried over? (Not individual failing tests, but whole areas.) Depends. It also might be more important to move on to other features to improve them.
Maybe some of these will be carried over? (Not individual failing tests, but whole areas.) Depends. It also might be more important to move on to other features to improve them.
January 5, 2026 at 8:32 PM
Any Focus Area that still needs work is considered for Interop 2026, but it’s not included automatically.
Maybe some of these will be carried over? (Not individual failing tests, but whole areas.) Depends. It also might be more important to move on to other features to improve them.
Maybe some of these will be carried over? (Not individual failing tests, but whole areas.) Depends. It also might be more important to move on to other features to improve them.
Happy new year! Ah, now we can checkout the results of Interop 2025 — and see the entire year on the dashboard.
wpt.fyi/interop-2025...
Safari might have started the year in last place, but we definitely ended in first.
(Interop Project tracks automated test pass rates for specific web API.)
wpt.fyi/interop-2025...
Safari might have started the year in last place, but we definitely ended in first.
(Interop Project tracks automated test pass rates for specific web API.)
January 5, 2026 at 8:15 PM
Happy new year! Ah, now we can checkout the results of Interop 2025 — and see the entire year on the dashboard.
wpt.fyi/interop-2025...
Safari might have started the year in last place, but we definitely ended in first.
(Interop Project tracks automated test pass rates for specific web API.)
wpt.fyi/interop-2025...
Safari might have started the year in last place, but we definitely ended in first.
(Interop Project tracks automated test pass rates for specific web API.)
Reposted by Jen Simmons
FINAAAAALLLYYYYYYY
Have you been wishing masonry layouts would just hurry up and arrive in CSS?? Well, happy holidays!
webkit.org/blog/17660/i...
webkit.org/blog/17660/i...
Introducing CSS Grid Lanes
It’s here!
webkit.org
December 30, 2025 at 8:34 PM
FINAAAAALLLYYYYYYY
Reposted by Jen Simmons
I enjoyed catching up on this post while I was on vacation.
Safari 26.2 is here with 65 features + 165 bug fixes — including field-sizing, Navigation API, Largest Contentful Paint, command & commandfor, CHIPS opt-in partitioned cookies, scrollend event, random(), WebGPU in WebXR, scrollbar-color, hidden=until-found and much more! webkit.org/blog/17640/w...
WebKit Features for Safari 26.2
Safari 26.2 is a big release.
webkit.org
January 5, 2026 at 3:39 PM
I enjoyed catching up on this post while I was on vacation.
Reposted by Jen Simmons
Have you been wishing masonry layouts would just hurry up and arrive in CSS?? Well, happy holidays!
webkit.org/blog/17660/i...
webkit.org/blog/17660/i...
Introducing CSS Grid Lanes
It’s here!
webkit.org
December 19, 2025 at 9:33 PM
Have you been wishing masonry layouts would just hurry up and arrive in CSS?? Well, happy holidays!
webkit.org/blog/17660/i...
webkit.org/blog/17660/i...
Reposted by Jen Simmons
Congrats to the Safari team. It's been years since Safari is the new IE meme was accurate.
December 20, 2025 at 1:28 AM
Congrats to the Safari team. It's been years since Safari is the new IE meme was accurate.
Check out all the revised demos of Grid Lanes in Safari Technology Preview 234!
webkit.org/demos/grid3/
webkit.org/demos/grid3/
December 20, 2025 at 1:31 AM
Check out all the revised demos of Grid Lanes in Safari Technology Preview 234!
webkit.org/demos/grid3/
webkit.org/demos/grid3/
More holiday cheer. For those of you asking about Safari’s “stable” Interop 2025 score…
December 20, 2025 at 1:19 AM
More holiday cheer. For those of you asking about Safari’s “stable” Interop 2025 score…
Reposted by Jen Simmons
The WebKit team is pushing out new features at lightning speed right now!
December 20, 2025 at 12:25 AM
The WebKit team is pushing out new features at lightning speed right now!
Did you see everything in Safari Technology Preview 234?
webkit.org/blog/17674/r...
It’s got a lot of new features including Grid Lanes, Threaded Scroll-driven Animations, seven new Web API, and more. Plus a TON of other improvements & fixes.
webkit.org/blog/17674/r...
It’s got a lot of new features including Grid Lanes, Threaded Scroll-driven Animations, seven new Web API, and more. Plus a TON of other improvements & fixes.
Release Notes for Safari Technology Preview 234
Safari Technology Preview Release 234 is now available for download for macOS Tahoe and macOS Sequoia.
webkit.org
December 20, 2025 at 12:22 AM
Did you see everything in Safari Technology Preview 234?
webkit.org/blog/17674/r...
It’s got a lot of new features including Grid Lanes, Threaded Scroll-driven Animations, seven new Web API, and more. Plus a TON of other improvements & fixes.
webkit.org/blog/17674/r...
It’s got a lot of new features including Grid Lanes, Threaded Scroll-driven Animations, seven new Web API, and more. Plus a TON of other improvements & fixes.
Have you been wishing masonry layouts would just hurry up and arrive in CSS?? Well, happy holidays!
webkit.org/blog/17660/i...
webkit.org/blog/17660/i...
Introducing CSS Grid Lanes
It’s here!
webkit.org
December 19, 2025 at 9:33 PM
Have you been wishing masonry layouts would just hurry up and arrive in CSS?? Well, happy holidays!
webkit.org/blog/17660/i...
webkit.org/blog/17660/i...
CSS `random()`, now in Safari 26.2.
Play around with it while waiting for other browsers to ship.
Play around with it while waiting for other browsers to ship.
Wasn't expecting how much fun random() is, it really opens up a ton of pure CSS creative possibilities.
Now you need custom functions, which combined with random() will enable all sorts of distributions, Perlin noise and more 😇
Now you need custom functions, which combined with random() will enable all sorts of distributions, Perlin noise and more 😇
December 16, 2025 at 5:36 PM
CSS `random()`, now in Safari 26.2.
Play around with it while waiting for other browsers to ship.
Play around with it while waiting for other browsers to ship.
Reposted by Jen Simmons
Do you have a favourite CSS one-liner?
December 16, 2025 at 1:37 PM
Do you have a favourite CSS one-liner?
Wondering what’s coming next in Safari 26.3? Well, check out the beta release notes: developer.apple.com/documentatio...
Safari 26.3 Beta Release Notes | Apple Developer Documentation
Released December 15, 2025 — 26.3 (20623.2.2)
developer.apple.com
December 16, 2025 at 5:32 PM
Wondering what’s coming next in Safari 26.3? Well, check out the beta release notes: developer.apple.com/documentatio...