🤩We just opened the Public Preview of our Reporting as a Service (RaaS) platform before the general release. Users from different countries are already accessing their personal Boards. Explore the platform by getting your own report: 👉 webperformancereport.com #webperf

Half a year ago, I published a pretty long paper about JPEG XL: arxiv.org/abs/2506.05987 I am happy to see that section 11.1 is already outdated!

Web Performance Calendar day 5 when @myshov.bsky.social shows us how to move heavy image decoding off the main thread. Drawing images in <canvas> freezing your UI and causing long tasks? Not anymore! calendar.perfplanet.com/2025/non-blo...

Speculation Rules on touch devices (where there's no hover) is a hard problem but it sounds like Chrome's making some good progress? htmhell.dev/adventcalend...

- Use a <picture> tag for semantic HTML - Sure, I’ll do it #SendMeCoffee 🫠

chrome-devtools-mcp v0.11.0 🎉 Features - emulation: add geolocation emulation tool - integrate DevTools issues into the console tools - support --user-data-dir github.com/ChromeDevToo... #DevTools #mcp #ai #Chrome

📣 New WebPerf Snippet Analyze all @media rules in CSS to identify classes and properties targeting viewports bigger than a specified breakpoint. Results are grouped by inline CSS and external files, with byte size estimates for potential mobile savings. #WebPerfSnippets #WebPerf

Análisis de Media Queries en CSS para Optimizar el Rendimiento joanleon.dev/posts/analis... 🇬🇧 version in thread #WebPerf #CSS #WebPerfSnippets #PerfTools #DevTools

📣 Updated my Resource Hints snippet for @chromedevtools.bsky.social Now detects common mistakes like: ❌ <link rel="preconnect dns-prefetch"> ❌ Non-standard rel values Perfect for auditing preload, prefetch, preconnect, etc webperf-snippets.nucliweb.net/Loading/Reso... #WebPerf #PerfTools

With @chromedevtools.bsky.social, we can streamline Web Performance Debugging with the help of the AI assistant #WebPerf #PerfTools #PerfDebugging

Dr. @guaca.bsky.social explains the diagnosis with @debugbear.com of our symptoms at DevFest Barcelona 2025 #DevFestBCN2025 #WebPerf #PerfTools #DevFest

Nuevo post "Más Allá de INP: LCP y el 90% invisible del rendimiento" de la serie de Long Animation frames API (LoAF) joanleon.dev/posts/loaf/m... #WebPerf #Performance #LoAF #LCP #CoreWebVitals

Effectively Monitoring Web Performance www.smashingmagazine.com/2025/11/effe... by @mattzeunert.com #WebPerf #Performance

I've updated the WebPerf Snippet "Find non Lazy Loaded Images outside of the viewport" to list images without loading="lazy". Now it shows: - Total number of images - Total file size - Individual details: URL, resolution & file size #WebPerf #WebPerfSnippets #PerfTools

Dark mode = On

Obs.js: context-aware web performance for everyone csswizardry.com/Obs.js/demo/ by @csswizardry.com #WebPerf #PerfTools #Performance #WebPerfSnippets

Our free HTML size analyzer can tell you what's taking up space in your HTML! Identify embedded images, fonts, or JavaScript hydration state. www.debugbear.com/html-size-an...

I reached peak performance using @chromedevtools.bsky.social's Performance panel! #DevBadges developers.google.com/profile/badg...

Chrome 143 will start rolling out today (most users get it next week). It includes a new set of options for your webperf traces — including saving sources & source maps: developer.chrome.com/docs/devtool... This makes it easier for those viewing traces outside of the page load to get more context.

AI assistance for performance developer.chrome.com/docs/devtool... by @matthiasrohmer.bsky.social #WebPerf #Performance #PerfTools #AI #PerfAI

Do you know the Web Performance Working Group? The mission of the Web Performance Working Group is to provide methods to measure aspects of application performance of user agent features and APIs. www.w3.org/webperf/ #WebPerf #Performance

HTML parsing speed depends a lot on how powerful the device that's visiting the website is. When I measure parse time on my laptop it takes under 7 milliseconds to process one megabyte of HTML. But on a low-end Android phone it takes 88 milliseconds! www.debugbear.com/blog/html-pa...

Quina il•lució em fa participar al #DevFest Girona 2025 ☺️ #GironaDevFest2025

I just wrote 'October 2025 Theme Vitals Update'. themevitals.com/newsletter/2... #webperf #Shopify

I'm excited to share a fantastic YouTube channel dedicated to Web Performance It's a project led by 2 major references in the Web Performance community, @guaca.bsky.social & @sia.codes www.youtube.com/@Performance... Subscribe to stay up-to-date & learn from the best in the community! #WebPerf

📣 New in Web Performance! We can now use the WebPerf Snippets for LCP & INP in Safari Technology Preview This allows us to measure 2 of the most critical Core Web Vitals metrics directly within Apple's browser Time to test! webperf-snippets.nucliweb.net #WebPerf #Safari #CoreWebVitals #LCP #INP

Debugging de INP: Del 'algo va lento' al 'esto es lo que lo rompe' Ahora nos enfrentamos a la tarea más importante: entender qué es lo que está causando esos frames lentos y, en última instancia, rompiendo nuestro INP. joanleon.dev/posts/loaf/d... #WebPerf #INP #LoAF #Performance

How to optimize SVG files: A complete guide for beginners penpot.app/blog/how-to-... by @laurakalbag.bsky.social #WebPerf #ImagePerf #SVG #Image

Fundamentos de Long Animation Frames API Descubre cómo Long Animation Frames API (LoAF) resuelve el mayor problema al debuggear INP: saber exactamente qué código causó una interacción lenta. Fundamentos, código práctico y conceptos clave joanleon.dev/posts/loaf/f... #WebPerf #INP #PerfTools #LoAF

"SSR is about ~SEO~ performance" - @rich-harris.dev #perfnow #WebPerf

If you are interested and want to learn about Web Performance, I recommend subscribing to @henrihelvetica.bsky.social's channel, where you will find high-quality videos from leading figures in the Web Performance community 📺 www.youtube.com/@HenriHelvet... #WebPerf #Performance #Learning #YouTube

New stickers for the WebPerf Snippets project webperf-snippets.nucliweb.net #WebPerf #WebPerfSnippets #PerfTools

We have new stickers 🥰

A little aftermovie to whet your appetite. www.youtube.com/watch?v=ByOC...

Huge thanks to @andydavies.me for mentioning the LoAF Helpers WebPerf Snippet at @perfnow.nl! Honored to be part of the amazing Web Performance community 🫶 🔗 webperf-snippets.nucliweb.net/Interaction/... #WebPerf #PerfNow #Performance #LoAF #INP #CoreWebVitals

Neat lil learning from today’s @perfnow.nl (via Umar Hansa): You can now throttle individual requests in Chrome! Neat for experimenting with stuff like - lazy-loading: does the UI look okay if this chunk takes MUCH longer to arrive - resilience: what happens if this specific CDN is extremely slow

Glad to announce that my team at @cloudflare.social released a 1.0.0 version of a cross-browser web performance testing agent that supports Chrome, Firefox, Safari and Edge. Thank you to @tkadlec.bsky.social for making it happen and writing most of the code so far! github.com/cloudflare/t...

Fellow #perfnow fellows, a reminder that PerfPlanet calendar is coming this December for another edition. And it needs YOU. Please ask if you have any contribution ideas or concerns calendar.perfplanet.com/contribute/

Awesome talk @michael-hladky.bsky.social at @perfnow.nl 👏 I 🫶 seeing people talk about optimizing #webperf with CSS Btw, regarding content-visibility, in this PR you can find a video explaining the issue where the browser frees nodes outside the viewport from memory github.com/nucliweb/rea...

Optimize images for sustainability "Ensure images, if required, are optimized, correctly formatted, and sized, with lazy loading as appropriate, and are managed effectively." - via @inesakrap.bsky.social's talk at @perfnow.nl w3c.github.io/sustainablew... #PerfNow #WebPerf #ImagePerf

This year, I’m following @perfnow.nl online. To all attendees, enjoy it! ☺️ #perfnow #WebPerf

Day 1! First talk by @tammyeverts.com. How fast is fast enough? #perfnow

BTW, here's our 2025 speakers starter pack: go.bsky.app/3tyzfGe

It's day 1 of #perfnow, I am live blogging conference notes here: stuart-mcmillan.com/blog/webperf... @perfnow.nl

New percentiles() method in WebPerf Snippets LoAF Helpers! Get P50, P75, P95, P99 stats for Long Animation Frames - perfect for RUM reporting without sending all frame data webperf-snippets.nucliweb.net/Interaction/... #WebPerf #WebPerfSnippets #PerfTools #INP #LoAF #JavaScript

Two of our attendees were refused a visa 😞 Still, that means we have two tickets left if anyone wants to come at this late stage. perfnow.nl/tickets.html

📣 New WebPerf Snippet LoAF Helpers: Advanced Debugging in DevTools webperf-snippets.nucliweb.net/Interaction/... #WebPerf #PerfTools #Performance #LoAF #INP

¿INP/LCP altos sin saber la causa? 😵‍💫 La nueva Long Animation Frames API (LoAF) te permite ver DENTRO de cada frame lento 🚀 Te enseño a usarla en vivo para cazar los scripts que arruinan la UX de tu web 🗓️ 30 Oct, 19:00 CET 🔗 www.meetup.com/es-ES/madrid... #WebPerf #INP #LoAF #JavaScript

Image format comparison: JPEG vs. PNG vs. WEBP vs. AVIF Great deep-dive into how image formats stack up — JPEG, PNG, WebP & AVIF — comparing size, quality & compression efficiency. 📸📊 A must-read for designers & web devs! photutorial.com/image-format... #Image #Performance #ImagePerf

After three years attending @perfnow.nl in person — the leading conference in the Web Performance community — this year I’ll be joining online. Huge thanks to the organizers for building such an inspiring community, full of talent, inclusion, collaboration, and friendship! #WebPerf #Perfnow