@csswizardry

🚀 Independent Web Performance Consultant • Speaker • Google Developer Expert, Web Performance • Accepting new clients • https://xitter.cf/t.co/dfDc69bpeD

 Leeds, England
csswizardry.com
Joined March 2009
  • Tweets48.7K
  • Following454
  • Followers65.3K
2.9KMedia
Harry Roberts retweeted
Harry Roberts
@csswizardryAug 18
For all you @SpeedCurve fans, meet LUX Sidecar: csswizardry.com/2026/08/intr…

Introducing LUX Sidecar: Your SpeedCurve Companion – CSS Wizardry

LUX Sidecar is a small SpeedCurve RUM plugin that adds browser and navigation context to your real-user performance data.

csswizardry.com
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Harry Roberts retweeted
Rick Brewster@rickbrewPDNMay 29
I GOT THE DOMAIN! I FINALLY GOT IT!!!!!!!!!!1 🥳🎉 Paint​.NET is now at paint.net! Well, it will be just as soon as I push all the buttons to migrate content and set up redirects from getpaint​.net etc. For now it's just a "hey go here" redirect page.

Paint.NET - Free Software for Digital Photo Editing

Paint.NET is free image and photo editing software for computers that run Windows.

paint.net
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Harry Roberts retweeted
Joost de Valk
@jdevalkMar 21
I built Yoast SEO. I ran my blog on WordPress for years. Then yesterday I moved it to static HTML. Everything that matters, SEO, search, schema, is still there. What I dropped was the overhead. Do you actually need a CMS? For quite some sites: no. joost.blog/do-you-need-a-cms…

Do you need a CMS? · Joost.blog

For twenty years, wanting a website meant needing a CMS. That's no longer true. The real question people ask now is simpler: how do I get my content on the web?

joost.blog
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The Fastest Site in the Tour de France via @csswizardry csswizardry.com/2025/07/the-…

The Fastest Site in the Tour de France – CSS Wizardry

How fast are pro cycling teams’ and manufacturers’ websites? A CrRRUX-powered deep dive into bike brand performance, visibility, and missed opportunities.

csswizardry.com
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Harry Roberts retweeted
Shift
@InfobipShift12 Sep 2025
🚀 ONLY 2 DAYS TO GO! Developers, we really hope you're buzzing with excitement, because we know we definitely are... 🫠 The countdown is almost over, and we absolutely can’t wait to open the gates to Višnjik Sports Hall! See you all soon at #ShiftZadar 2025! 💚 shift.infobip.com/
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Harry Roberts retweeted
Harry Roberts
@csswizardry19 Aug 2025
I love @ChromeDevTools’s Snippets, but they don’t take parameters which means you need to change the snippet itself every time. One way around it is to take input from `prompt()`!
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Harry Roberts retweeted
Harry Roberts
@csswizardry5 Sep 2025
🖼️ Chrome and Firefox both support ::after on alt text:
Chrome: Screenshot of a JS Bin demo. The HTML defines an image with alt="This image deliberately 404s" and a missing src. CSS uses img[alt]::after with content: " [attr(src)]". On the right, the rendered output shows “This image deliberately 404s [deliberate-404.jpg]” in italic monospace.

ALT Chrome: Screenshot of a JS Bin demo. The HTML defines an image with alt="This image deliberately 404s" and a missing src. CSS uses img[alt]::after with content: " [attr(src)]". On the right, the rendered output shows “This image deliberately 404s [deliberate-404.jpg]” in italic monospace.

Firefox: Screenshot of a JS Bin demo. The HTML defines an image with alt="This image deliberately 404s" and a missing src. CSS uses img[alt]::after with content: " [attr(src)]". On the right, the rendered output shows “This image deliberately 404s [deliberate-404.jpg]” in italic monospace.

ALT Firefox: Screenshot of a JS Bin demo. The HTML defines an image with alt="This image deliberately 404s" and a missing src. CSS uses img[alt]::after with content: " [attr(src)]". On the right, the rendered output shows “This image deliberately 404s [deliberate-404.jpg]” in italic monospace.

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Harry Roberts retweeted
LaurieWired
@lauriewired6 Sep 2025
Replying to @N_LgMa
why don't you check my bio
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Harry Roberts retweeted
JSter@jsterlibs5 Sep 2025
Making Sense of the Performance Extensibility API buff.ly/hPL0wwb
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Harry Roberts retweeted
Harry Roberts
@csswizardry28 Aug 2025
🔍 Obs.js 0.2.1 is now officially open sourced. I would really love early feedback and especially any showcases of folk using it—I’ll add any of your examples to the demo page. csswizardry.com/Obs.js/demo/

Obs.js – context-aware web performance for everyone

Obs.js reads device and network signals and allows you to build adaptive user experiences.

csswizardry.com
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Harry Roberts retweeted
Harry Roberts
@csswizardry3 Sep 2025
Is anyone currently, deliberately, voluntarily NOT using Tailwind CSS for their work?
54%No, I am using Tailwind
46%Yes, I am using…
743 votes • Final results
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Replying to @csswizardry
This made it to WordPress core thanks to you! github.com/WordPress/wordpre…

Add sourceURL to inline script and style tags by sirreal · Pull Request #9628 · WordPress/wordpre...

Trac ticket: https://core.trac.wordpress.org/ticket/63887 Script and style tags can add a sourceURL comment to name them for developer tools. This is similar to sourceMappingURL that are often use...

github.com
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Harry Roberts retweeted
Harry Roberts
@csswizardry11 Aug 2025
🤯 I can’t believe I only learned this yesterday: `//# sourceURL=inline:foo.js`
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I'm in ☺️
Harry Roberts
@csswizardry8 Aug 2025
🚀 Making @fastly a second faster. Subscribers find out how on Monday. 👉 csswizardry.gumroad.com/l/su…
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Harry Roberts retweeted
Harry Roberts
@csswizardry14 Jul 2025
🧭 Core Web Vitals are coming to Safari—get prepared! csswizardry.com/workshops/co…

Core Web Vitals on iOS – CSS Wizardry

Arrange a one-day workshop and get hands-on with Core Web Vitals in Safari

csswizardry.com
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Harry Roberts retweeted
Harry Roberts
@csswizardry27 Jun 2025
📱 iOS users: is your default browser Safari or something else? Explain why.
58%Safari
42%Other
625 votes • Final results
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form onSubmit > form submit button onClick alexcarpenter.me/notes/2025-…

Alex Carpenter

Staff UI Engineer at Clerk

alexcarpenter.me
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anyone interested in sponsoring for an over-the-top arm local machine for Porffor testing at scale locally? or should I just try some cloud provider?
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In Pieces turns 10 years old. 🐬🎂 species-in-pieces.com
🐝 Bryan James
@WengersToyBus17 Mar 2015
In Pieces – 30 species, 30 pieces. Explore an interactive exhibition of unique but unfortunately endangered species. species-in-pieces.com

In Pieces – 30 Species, 30 Pieces. 1 Fragmented Survival.

30 species, 30 pieces. In Pieces is an interactive exhibition of 30 of the world’s most interesting but unfortunately endangered species — their survivals laying literally, in pieces. Explore...

species-in-pieces.com
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Harry Roberts retweeted
Harry Roberts
@csswizardry27 Nov 2024
If you need a simple HTML spoiler-type element (that doesn’t appear in Google rich results), you might want something like this:
<div data-nosnippet> <details> <summary>Like spoilers? See the answer.</summary> <p>•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••</p> </details> </div>

ALT <div data-nosnippet> <details> <summary>Like spoilers? See the answer.</summary> <p>•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••</p> </details> </div>

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