Michaël Vanderheyden
@th3s4mur41.me
Lead UX Engineer & Accessibility Specialist @ cycos, an Atos Business
#CPWA #WebDev #A11y #CSS
Martial arts lover | Shotokan Karate black belt | BJJ practitioner | Bikejöring
https://th3s4mur41.me
#CPWA #WebDev #A11y #CSS
Martial arts lover | Shotokan Karate black belt | BJJ practitioner | Bikejöring
https://th3s4mur41.me
Reposted by Michaël Vanderheyden
2/2
• Drop-down: adrianroselli.com/2020/03/stop...
• Grid: adrianroselli.com/2024/07/be-c...
• Menu: adrianroselli.com/2023/05/be-c...
• Pop-up: adrianroselli.com/2021/07/stop...
#HTML #accessibility #a11y
• Drop-down: adrianroselli.com/2020/03/stop...
• Grid: adrianroselli.com/2024/07/be-c...
• Menu: adrianroselli.com/2023/05/be-c...
• Pop-up: adrianroselli.com/2021/07/stop...
#HTML #accessibility #a11y
Stop Using ‘Drop-down’
TL;DR: Stop using the word drop-down. Instead choose a term that accurately describes the control you want. I have worked both with native platform developers and web developers. While control names m...
adrianroselli.com
February 18, 2026 at 3:10 PM
2/2
• Drop-down: adrianroselli.com/2020/03/stop...
• Grid: adrianroselli.com/2024/07/be-c...
• Menu: adrianroselli.com/2023/05/be-c...
• Pop-up: adrianroselli.com/2021/07/stop...
#HTML #accessibility #a11y
• Drop-down: adrianroselli.com/2020/03/stop...
• Grid: adrianroselli.com/2024/07/be-c...
• Menu: adrianroselli.com/2023/05/be-c...
• Pop-up: adrianroselli.com/2021/07/stop...
#HTML #accessibility #a11y
Reposted by Michaël Vanderheyden
Here are a few things I plan to cover in the Poetic #CSS course, but I'd love your input and questions! Where are you having the most issues, what piques your curiosity, and where do you have questions?
Feel free to vote for multiple in the replies, or suggest other topics & specific questions.
Feel free to vote for multiple in the replies, or suggest other topics & specific questions.
February 17, 2026 at 7:23 PM
Here are a few things I plan to cover in the Poetic #CSS course, but I'd love your input and questions! Where are you having the most issues, what piques your curiosity, and where do you have questions?
Feel free to vote for multiple in the replies, or suggest other topics & specific questions.
Feel free to vote for multiple in the replies, or suggest other topics & specific questions.
Reposted by Michaël Vanderheyden
Responsive type doesn’t have to be complicated. @miriam.codes will show @jamessw.com and me how we can get great results from a few lines of readable code on the next Winging It on Thursday, February 19 at 1pm ET
www.youtube.com/live/B-r6wem...
www.youtube.com/live/B-r6wem...
Responsive Type Doesn’t Have To Be Complicated
YouTube video by Winging It
www.youtube.com
February 16, 2026 at 8:36 PM
Responsive type doesn’t have to be complicated. @miriam.codes will show @jamessw.com and me how we can get great results from a few lines of readable code on the next Winging It on Thursday, February 19 at 1pm ET
www.youtube.com/live/B-r6wem...
www.youtube.com/live/B-r6wem...
Reposted by Michaël Vanderheyden
This is to collect research for HTML input pickers such as date, time, datetime and colour. "Please send us examples of good (or bad) ones. Even if they have extra functionality that doesn't exist yet (e.g. date ranges, perhaps we can add that in)." github.com/openui/open-...
Research Issue for pickers · Issue #1371 · openui/open-ui
This is to collect research for pickers such as date, time, datetime and colour. Please send us examples of good (or bad) ones. Even if they have extra functionality that doesn't exist yet (e.g. da...
github.com
February 13, 2026 at 7:06 PM
This is to collect research for HTML input pickers such as date, time, datetime and colour. "Please send us examples of good (or bad) ones. Even if they have extra functionality that doesn't exist yet (e.g. date ranges, perhaps we can add that in)." github.com/openui/open-...
Reposted by Michaël Vanderheyden
WCAG updates reflect a growing understanding that accessibility barriers are moving standards toward more outcomes-based models; the focus is now on how people interact with digital experiences.
Learn what's shaping accessible experiences: https://f.mtr.cool/kogiqkupcd
#WCAG #a11y
Learn what's shaping accessible experiences: https://f.mtr.cool/kogiqkupcd
#WCAG #a11y
February 13, 2026 at 3:04 PM
WCAG updates reflect a growing understanding that accessibility barriers are moving standards toward more outcomes-based models; the focus is now on how people interact with digital experiences.
Learn what's shaping accessible experiences: https://f.mtr.cool/kogiqkupcd
#WCAG #a11y
Learn what's shaping accessible experiences: https://f.mtr.cool/kogiqkupcd
#WCAG #a11y
Safari doesn’t make scrollable elements keyboard‑focusable, which breaks WCAG 2.2’s Keyboard criterion.
That means keyboard users can’t fully read code blocks in docs.
I wrote about the issue and a temporary workaround until WebKit fixes it:
th3s4mur41.me/blog/scroll-...
#A11y #WCAG #WebDev
That means keyboard users can’t fully read code blocks in docs.
I wrote about the issue and a temporary workaround until WebKit fixes it:
th3s4mur41.me/blog/scroll-...
#A11y #WCAG #WebDev
Making Scrollable Code Blocks Accessible | Th3S4mur41
Fix keyboard accessibility gaps in Safari: learn why scrollable code blocks need focus and how a small polyfill makes them accessible for keyboard users.
th3s4mur41.me
February 13, 2026 at 12:14 PM
Safari doesn’t make scrollable elements keyboard‑focusable, which breaks WCAG 2.2’s Keyboard criterion.
That means keyboard users can’t fully read code blocks in docs.
I wrote about the issue and a temporary workaround until WebKit fixes it:
th3s4mur41.me/blog/scroll-...
#A11y #WCAG #WebDev
That means keyboard users can’t fully read code blocks in docs.
I wrote about the issue and a temporary workaround until WebKit fixes it:
th3s4mur41.me/blog/scroll-...
#A11y #WCAG #WebDev
@biomejs.dev is a fast, unified alternative to the usual Prettier + ESLint + Stylelint setup. The question now is how opinionated rules (like #defensiveCSS) should fit in — plugins or opt‑in core domains.
If better CSS linting matters to you, feel free to join or upvote:
github.com/biomejs/biom...
If better CSS linting matters to you, feel free to join or upvote:
github.com/biomejs/biom...
Biome plugins distribution · biomejs biome · Discussion #6265
Since v2, Biome now supports plugins via GritQL, however users can't distribute/share these plugins at the moment. The initial idea behind this plugin system was to provide users the ability to cre...
github.com
February 11, 2026 at 8:50 AM
@biomejs.dev is a fast, unified alternative to the usual Prettier + ESLint + Stylelint setup. The question now is how opinionated rules (like #defensiveCSS) should fit in — plugins or opt‑in core domains.
If better CSS linting matters to you, feel free to join or upvote:
github.com/biomejs/biom...
If better CSS linting matters to you, feel free to join or upvote:
github.com/biomejs/biom...
Reposted by Michaël Vanderheyden
With $10 off, that makes it only $29... plus you can take my other course on there too... and any of their other courses.
Sounds like a pretty good deal to me 😅
Sounds like a pretty good deal to me 😅
My new CSS course is now live on @frontendmasters.com! Learn the essentials, including responsive layouts, typography, animations, and more.
Save $10 on your first month: frontendmasters.com/courses/css-... (affiliate link, so it helps support me too 😊)
Save $10 on your first month: frontendmasters.com/courses/css-... (affiliate link, so it helps support me too 😊)
Learn CSS & Responsive Design Fundamentals
Learn the essentials of typography, responsive grid layout, animations, and form styling. By the end, you'll have the foundation to dive into your next vanilla CSS codebase or use utility-first approa...
frontendmasters.com
February 10, 2026 at 7:39 PM
With $10 off, that makes it only $29... plus you can take my other course on there too... and any of their other courses.
Sounds like a pretty good deal to me 😅
Sounds like a pretty good deal to me 😅
Reposted by Michaël Vanderheyden
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...
Reposted by Michaël Vanderheyden
💡 CSS Tip!
Have you ever tried to use "auto" within clamp()? Unfortunately, it doesn't work, but it's now possible using the new calc-size()!
css-tip.com/clamp-auto/
The same applies to all the sizing values (min-content, max-content, fit-content, etc.)
Have you ever tried to use "auto" within clamp()? Unfortunately, it doesn't work, but it's now possible using the new calc-size()!
css-tip.com/clamp-auto/
The same applies to all the sizing values (min-content, max-content, fit-content, etc.)
February 5, 2026 at 11:10 AM
💡 CSS Tip!
Have you ever tried to use "auto" within clamp()? Unfortunately, it doesn't work, but it's now possible using the new calc-size()!
css-tip.com/clamp-auto/
The same applies to all the sizing values (min-content, max-content, fit-content, etc.)
Have you ever tried to use "auto" within clamp()? Unfortunately, it doesn't work, but it's now possible using the new calc-size()!
css-tip.com/clamp-auto/
The same applies to all the sizing values (min-content, max-content, fit-content, etc.)
Reposted by Michaël Vanderheyden
"Exclusion happens when we solve problems using our own biases. We seek out exclusions, and use them as opportunities to create new and better experiences." ♥️
— The New Inclusive Design website from Microsoft inclusive.microsoft.design
— The New Inclusive Design website from Microsoft inclusive.microsoft.design
Microsoft Inclusive Design
Microsoft Inclusive Design is a practice that anyone who creates and manages products and services can use to build more inclusive experiences for everyone. Get the principles, guidebooks, workshop to...
inclusive.microsoft.design
February 5, 2026 at 8:32 AM
"Exclusion happens when we solve problems using our own biases. We seek out exclusions, and use them as opportunities to create new and better experiences." ♥️
— The New Inclusive Design website from Microsoft inclusive.microsoft.design
— The New Inclusive Design website from Microsoft inclusive.microsoft.design
Reposted by Michaël Vanderheyden
Reposted by Michaël Vanderheyden
Progressive enhancement matters, and makes total sense. Do you try to use native HTML elements whenever you can?
🔴 Check out Theodore sharing tips and tricks from You Don't Need JavaScript on WeAreDevelopers LIVE at www.wearedevelopers.com/en/videos/17...
🔴 Check out Theodore sharing tips and tricks from You Don't Need JavaScript on WeAreDevelopers LIVE at www.wearedevelopers.com/en/videos/17...
January 31, 2026 at 12:01 PM
Progressive enhancement matters, and makes total sense. Do you try to use native HTML elements whenever you can?
🔴 Check out Theodore sharing tips and tricks from You Don't Need JavaScript on WeAreDevelopers LIVE at www.wearedevelopers.com/en/videos/17...
🔴 Check out Theodore sharing tips and tricks from You Don't Need JavaScript on WeAreDevelopers LIVE at www.wearedevelopers.com/en/videos/17...
Reposted by Michaël Vanderheyden
Help prioritize the web features you need most → goo.gle/4iVDhCk
The WebDX Community Group is launching a direct way for you to upvote features on sites like Can I Use and web.dev to signal demand to browser vendors.
The WebDX Community Group is launching a direct way for you to upvote features on sites like Can I Use and web.dev to signal demand to browser vendors.
January 30, 2026 at 5:51 PM
Help prioritize the web features you need most → goo.gle/4iVDhCk
The WebDX Community Group is launching a direct way for you to upvote features on sites like Can I Use and web.dev to signal demand to browser vendors.
The WebDX Community Group is launching a direct way for you to upvote features on sites like Can I Use and web.dev to signal demand to browser vendors.
Reposted by Michaël Vanderheyden
🎉 Live from the CSS WG F2F: We just agreed to support multiple borders and outlines per element, comma-separated!
But we can’t decide on the order: inside out or outside in?
What feels more natural to you, A or B?
(it needs to be the same across borders and outlines or different box-sizing values)
But we can’t decide on the order: inside out or outside in?
What feels more natural to you, A or B?
(it needs to be the same across borders and outlines or different box-sizing values)
January 28, 2026 at 10:03 PM
🎉 Live from the CSS WG F2F: We just agreed to support multiple borders and outlines per element, comma-separated!
But we can’t decide on the order: inside out or outside in?
What feels more natural to you, A or B?
(it needs to be the same across borders and outlines or different box-sizing values)
But we can’t decide on the order: inside out or outside in?
What feels more natural to you, A or B?
(it needs to be the same across borders and outlines or different box-sizing values)
Reposted by Michaël Vanderheyden
My book, Accessibility For Everyone, is now free and online as a website.
accessibilityforeveryone.site
The book was first published by A Book Apart in 2017 but it holds up! It covers web accessibility for designers, developers, content folks, and really everyone who works in tech.
accessibilityforeveryone.site
The book was first published by A Book Apart in 2017 but it holds up! It covers web accessibility for designers, developers, content folks, and really everyone who works in tech.
Accessibility For Everyone by Laura Kalbag
Read the book online for free.
accessibilityforeveryone.site
January 27, 2026 at 1:14 PM
My book, Accessibility For Everyone, is now free and online as a website.
accessibilityforeveryone.site
The book was first published by A Book Apart in 2017 but it holds up! It covers web accessibility for designers, developers, content folks, and really everyone who works in tech.
accessibilityforeveryone.site
The book was first published by A Book Apart in 2017 but it holds up! It covers web accessibility for designers, developers, content folks, and really everyone who works in tech.
Reposted by Michaël Vanderheyden
99% across the board! A pretty nice way to wrap the Interop 2025 project up.
Interop 2026 is about ready to launch very soon too.
So, even more web platform features will get a boost soon!
If only we could do this with ALL features of the web 😀
Interop 2026 is about ready to launch very soon too.
So, even more web platform features will get a boost soon!
If only we could do this with ALL features of the web 😀
January 22, 2026 at 6:14 PM
99% across the board! A pretty nice way to wrap the Interop 2025 project up.
Interop 2026 is about ready to launch very soon too.
So, even more web platform features will get a boost soon!
If only we could do this with ALL features of the web 😀
Interop 2026 is about ready to launch very soon too.
So, even more web platform features will get a boost soon!
If only we could do this with ALL features of the web 😀
Reposted by Michaël Vanderheyden
A really common user interface pattern is a big clickable area, such as a card. Sometimes you need controls within that card that are also clickable. There's lots of ways to do it wrong, but fret not, @ericwbailey.website is here to show you how to do it right.
piccalil.li/blog/accessi...
piccalil.li/blog/accessi...
Accessible faux-nested interactive controls
A really common user interface pattern is a big clickable area, such as a card. Sometimes you need controls within that card that are also clickable. There's lots of ways to do it wrong, but fret not,...
piccalil.li
January 15, 2026 at 12:18 PM
A really common user interface pattern is a big clickable area, such as a card. Sometimes you need controls within that card that are also clickable. There's lots of ways to do it wrong, but fret not, @ericwbailey.website is here to show you how to do it right.
piccalil.li/blog/accessi...
piccalil.li/blog/accessi...
New post: Contrast: beyond WCAG compliance.
Contrast is one of the better‑known accessibility checks and easy to automate — but “passing” doesn’t always mean readable.
I show examples, explain why APCA works better, and how to use it today.
th3s4mur41.me/blog/a11y-ti...
#a11y #WCAG #APCA #contrast
Contrast is one of the better‑known accessibility checks and easy to automate — but “passing” doesn’t always mean readable.
I show examples, explain why APCA works better, and how to use it today.
th3s4mur41.me/blog/a11y-ti...
#a11y #WCAG #APCA #contrast
Contrast: Beyond WCAG Compliance | Th3S4mur41.me
Discover why APCA offers a more perceptually accurate approach to color contrast than traditional WCAG standards for better readability.
th3s4mur41.me
January 15, 2026 at 12:07 PM
New post: Contrast: beyond WCAG compliance.
Contrast is one of the better‑known accessibility checks and easy to automate — but “passing” doesn’t always mean readable.
I show examples, explain why APCA works better, and how to use it today.
th3s4mur41.me/blog/a11y-ti...
#a11y #WCAG #APCA #contrast
Contrast is one of the better‑known accessibility checks and easy to automate — but “passing” doesn’t always mean readable.
I show examples, explain why APCA works better, and how to use it today.
th3s4mur41.me/blog/a11y-ti...
#a11y #WCAG #APCA #contrast
Reposted by Michaël Vanderheyden
🔥 New blog post: Web dependencies are broken. Can we fix them?
“Dear #JS ecosystem, I love you, but you have a dependency management problem when it comes to the Web, and the time has come for an intervention.”
Read more: lea.verou.me/blog/2026/we...
“Dear #JS ecosystem, I love you, but you have a dependency management problem when it comes to the Web, and the time has come for an intervention.”
Read more: lea.verou.me/blog/2026/we...
Web dependencies are broken. Can we fix them? • Lea Verou
Dear JS ecosystem, I love you, but you have a dependency management problem when it comes to the Web, and the time has come for an intervention.
lea.verou.me
January 7, 2026 at 7:11 PM
🔥 New blog post: Web dependencies are broken. Can we fix them?
“Dear #JS ecosystem, I love you, but you have a dependency management problem when it comes to the Web, and the time has come for an intervention.”
Read more: lea.verou.me/blog/2026/we...
“Dear #JS ecosystem, I love you, but you have a dependency management problem when it comes to the Web, and the time has come for an intervention.”
Read more: lea.verou.me/blog/2026/we...
Call for Speakers for @wearedevelopers.bsky.social World Congress 2026 - Europe is still open until Friday on Sessionize and I've just submitted a session!
sessionize.com/wearedevelop...
sessionize.com/wearedevelop...
WeAreDevelopers World Congress 2026 - Europe: Call for Speakers
The World's Leading Event for Developers, AI Innovators & Tech LeadersHey developers,The global developer community meets again at the WeAreDevelopers...
sessionize.com
January 12, 2026 at 9:59 AM
Call for Speakers for @wearedevelopers.bsky.social World Congress 2026 - Europe is still open until Friday on Sessionize and I've just submitted a session!
sessionize.com/wearedevelop...
sessionize.com/wearedevelop...
Reposted by Michaël Vanderheyden
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 Michaël Vanderheyden
Been catching up on @amyhupe.bsky.social's wonderful Systems of Harm podcast and really enjoyed this episode with @tink.uk. Covers a lot from #a11y to #AI and I always find Léonie's perspective valuable.
systems-of-harm.fireside.fm/ep2-leonie-w...
systems-of-harm.fireside.fm/ep2-leonie-w...
Design systems and accessibility with Léonie Watson
How can design systems help us to create more accessible user experiences? How can we win hearts and minds in the fight to create more equitable experiences for disabled people? Will AI help or hinder...
systems-of-harm.fireside.fm
December 19, 2025 at 7:46 PM
Been catching up on @amyhupe.bsky.social's wonderful Systems of Harm podcast and really enjoyed this episode with @tink.uk. Covers a lot from #a11y to #AI and I always find Léonie's perspective valuable.
systems-of-harm.fireside.fm/ep2-leonie-w...
systems-of-harm.fireside.fm/ep2-leonie-w...
TIL the first rule of ARIA—don’t use ARIA—applies to aria-busy too. Even when used right, it’s inconsistent across assistive tech. Thanks @gerardkcohen.me for the insight!
gerardkcohen.me/writing/2025...
#a11y #aria #aria-busy #TIL
gerardkcohen.me/writing/2025...
#a11y #aria #aria-busy #TIL
aria-busy is not your friend | Writing | gerardkcohen.me
aria-busy is a misunderstood and misused property. Learn what it really does and whether or not you should be using it.
gerardkcohen.me
December 12, 2025 at 12:57 PM
TIL the first rule of ARIA—don’t use ARIA—applies to aria-busy too. Even when used right, it’s inconsistent across assistive tech. Thanks @gerardkcohen.me for the insight!
gerardkcohen.me/writing/2025...
#a11y #aria #aria-busy #TIL
gerardkcohen.me/writing/2025...
#a11y #aria #aria-busy #TIL