Good blog post from Carlos (a colleague) about a new proposed addition to Compression Dictionaries allowing short-lived HTML pages to continue to be used as compression dictionaries for longer:
dev.to/carlosmateom...
#webperf
Well you can shrink it down to just the icons if you want to get the full @johnmu.com experience. But even then this dog is too old to learn new tricks it seems!
You were always a man of impeccable taste Dave!
You had to take it one step too far.
Have you tried the Lynx browser? 😀
OK I've tried it for a while, but I can't get with Vertical tabs. Old skool Horizontal tabs FTW for me...
WebPerf Snippets and Agent SKILLs: deterministic audits with Chrome DevTools MCP
Claude Code report showing Usercentrics scripts causing performance issues by combining 'preload' and 'async'. It recommends removing preloads or using fetchpriority='low' to avoid competing with critical LCP resources.
I've been using WebPerf Snippets in my audits for years.
Scripts to measure LCP, INP, CLS, TTFB, Render Blocking...
The next step: turning them into tools an AI agent can use autonomously.
But there's a design decision that makes all the difference.
🧵
#WebPerf #WebPerformance #AI #DevTools #MCP
Congrats! Sounds like a perfect match.
JavaScript's date object has been tricky for years, but that is changing.
The NEW Temporal API brings,
🌍 Easily handle time zones
📆 Precise date math
🕒 Parse ISO strings without errors
⌛ Durations, date ranges, and more.
Start experimenting 👇
developer.mozilla.org/en-US/docs/...
Dear God, what have we done? Maybe adding this was a mistake?
But seriously clever (mis)use of this! And surprisingly little code!
A clean looking graphic with sharp lines and crisp colour
The same graphic, but muddy and blocky. The previously sharp lines are blurry.
I think it's often overlooked that AVIF is also really good at flat colour & sharp edges.
Don't go straight for a lossless format just because it's the kind of image that would look bad as a JPEG.
Here's an 11kb image as an AVIF, vs JPEG XL.
Good choice! From both sides :-) Congrats.
New alternatives to innerHTML (setHTML) by @ollie-williams.bsky.social
I get this is hard, and being conservative is usually a good thing, when it comes to avoiding assumptions, but this just seems too far off, so being a useless measure...
</rant> (which has 0% support btw).
The <a> element is 96.76% of "all users" for example, showing how meaningless this is. If you don't support that, then you don't support HTML IMHO.
In fact <html> is also 96.76% (but hey it wasn't in the first version of HTML). As is <h1> - <h6> (which were in the first version).
I don't get that 5%. It seems incredibly high.
The difference between "all users" (96.3% for fetch) and "all tracked" (99.43%) on caniuse is apparently if it's an untracked browser the assumption is it's unsupported but not sure that's a valid assumption and isn't way overly conservative.
Ahhh to be back home after a quick jaunt to London for #SotB. Great to catch up with some familiar faces and meet up with some online people for the first time IRL! Conference was pretty good too 😀
Ha ha. Was thinking that earlier.
Still terrible @zachleat.com !
Strong showing from the Chrome team! Excited for my first SotB!!
Well, that was a productive train ride…
In the previous post, I explained how to hide presentational SVGs using aria-hidden="true".
That's a reliable technique, but sometimes I see developers use role="presentation" instead, which may or may not work as expected.
matuzo.at/blog/2026/ro...
Block announced the layoffs in conjunction with its fourth-quarter earnings results. The payments company reported adjusted earnings per share of 65 cents on revenue of $6.25 billion, while analysts estimated 65 cents per share and $6.24 billion, according to LSEG. Gross profit increased 24% from a year earlier to $2.87 billion. For the full year, the company said it sees adjusted earnings per share of $3.66. Analysts anticipated $3.22 per share, according to LSEG.
Equally depressing for such a drastic cut given the reported financials:
It is depressing to see the positive impact sacking people has on shares.
Block shares soar 24% as company slashes workforce by nearly half www.cnbc.com/2026/02/26/b...
Hi friends I just got laid off along with 40% of Block. No idea what comes next, but if you have need for a Principal Frontend Engineer hit me up!
Urgh sorry to hear that Katie. Take some time and hope you get sorted out quickly when ready.
☝️ this is the way. On both points.
Ever wanted a comprehensive guide to DevTools and debugging front ends? Check out this ebook that Lala Hakobyan just launched:
github.com/lala-hakobya...
I’m impressed!!
Container Timing - a new W3C performance metric - has migrated from Bloomberg to the WICG Github org 🎉
@jason-williams.co.uk made the Bloomberg Terminal use this web metric to measure human-perceived time to start apps. We've found it more useful than existing metrics.
github.com/WICG/contain...
Oh and that weekly newsletter I was talking about full of tips and tricks like this:
webweekly.email
// get all resources window.performance.getEntriesByType('resource') // only consider the blocking ones .filter(({renderBlockingStatus}) => renderBlockingStatus === 'blocking') // log their names .forEach(({name}) => console.log(name)) // Logs: https://your-site.com/styles.css
Missed this one but thanks to @stefanjudis.com 's weekly newsletter (you should sign up btw) I saw his own post on how to identify render-blocking resources in Chrome: www.stefanjudis.com/blog/how-to-...
Try it in the console now! (code in Alt text)
<video loading="lazy" autoplay playsinline muted controls src="path/to/sloth.webm" poster="path/to/sloth.jpg"></video>
Lazy-loaded video/auto elements are finally coming to the web! 🎉
scottjehl.com/posts/lazy-m...
Working with the fantastic Governor of Louisiana, Jeff Landry, we are going to send a great hospital boat to Greenland to take care of the many people who are sick, and not being taken care of there. It's on the way!!! President DJT
Healthcare in Greenland is publicly funded, free at the point of use, and despite geographical challenges considered very good.
Healthcare costs in the USA are extortionate and responsible for 60% of all US bankruptcies.
So maybe Denmark should be sending hospital ships the other way.
