Ever wish HTTP status codes were easier to remember? 🖼️ Check out this MDN cheatsheet that pairs each status code with an emoji to help you visualize what each one means, from 200 OK ✅ to 418 I’m a teapot 🫖 Check it out 👇

Which image format really gives you the best balance between speed, size, and quality? 🤔 In this hands-on MDN post, Polina Gurtovaia runs real compression experiments (AVIF vs. JPEG 🐿️) and breaks down how to pick the right codec for your workflow. developer.mozilla.org/en-US/blog/...

I’m excited about this! Firefox leadership is doing an AMA on r/firefox 🔥 If you didn’t know, r/firefox is a long-standing, independently run Reddit community that’s been around since 2008, and still gets nearly half a million weekly visitors.

I’ve been playing FIFA since ‘08. Built a startup on top of FIFA 17-19. Sweated through Weekend Leagues. And now… my favorite browser is in the new FIFA. Firefox branding just landed in EA SPORTS FC™ 26 ⚽🧡 Big win for the team, and a personal full-circle moment.

The Mozilla Support platform (aka SUMO) gets 20M+ visits a month — it’s where Firefox users go when they need help, guidance, or just a little browser magic. But SUMO isn’t just docs. It’s a global community. And now, it’s your turn to jump in!

Got mail 📬 The awesome folks at @fiberplane and @Cloudflare sent over this sticker sheet + a super kind note after I joined VibeSummer and built an MCP using their codegen tool 💥 Challenge 1 was 🔥 Their DX made it really fun. Wanna see what I built? 👀

Ever wanted to stream data into a fetch() request? We’re exploring better support for using ReadableStream as a request body, and we’d love your input. It’s a quick 1–2 min survey, and your feedback could shape what browsers prioritize next 👇 survey.alchemer.com/s3/8460326/...

I’m joining The UX Show for Ep. 4 — streaming October 14! 🎙 We’ll talk about: → MDN Fred 💙 → Open source & contribution models → UX at the core of web dev 📍 Live on YT (@GDGSpain) & Google Dev Discord 🕑 2:00 PM UTC Come hang out! Hosted by Yash, Giga, Victor & Andreu 🙌

Have thoughts on using ReadableStream as a request body in fetch()? We're running a quick survey (1–2 mins) to gauge interest, it'll help shape what browser folks prioritize next. If you care about streaming uploads or fetch, this is for you 👇 survey.alchemer.com/s3/8460326/...

Web devs, hear me out! 👋 We're running a short survey (1–2 min) to understand interest in using ReadableStream as a request body in the Fetch API. Please help us guide implementation priorities, especially around support & use cases. Survey here 👇 survey.alchemer.com/s3/8460326/...

This chart is wild. GitHub Copilot is doing $800M in revenue, more than the next 3 combined. But what really stands out to me is how many niche startups are in the mix. We're watching the category go from novelty → infrastructure. Lovable. Poolside. Tabby. Sourcegraph. Relicx.

Interop 2026 is open for proposals! 🧪 If there’s a feature that’s already standardized and well-tested; but still feels like a gamble across browsers — this is your moment. Help shape the priorities for the next year of browser work. File a proposal 👇 github.com/web-platfor...

One of the biggest lessons from the modern internet: Depth > reach Community > audience Whether you're running a product, project, or publication. The stuff that lasts is built with people, not just for them.

I was listening to the latest Vergecast episode on my way to work with the creators of Cracking the Cryptic, and I can’t stop thinking about it. Two middle-aged puzzle lovers. A YouTube channel solving Sudoku variants. Now? A thriving, kind, 40,000+ strong community on Discord.

I've got a bunch of lovely folks in my DMs asking this, and what to cover, so I figured I'll share what does a GitHub Work Week actually look like? 🧵

Every 6 months, I run a GitHub Work Week with my community, and it’s honestly one of the best things we do. We close stale issues, PRs, docs, and rethink our community experience. I like to call it “community debt” — the invisible stuff that piles up while you're busy building.

You still have time, The State of HTML 2025 survey is live. Browser vendors use this data to prioritize features, fix incompatibilities. Standards bodies use it too. It’s not just a survey, it’s influence. Take 10 minutes. Share what you care about. 👇 stateofhtml.com/en-US

Being vulnerable on social media is hard for me. Maybe it’s the age I grew up in. Maybe it’s my privacy-focused brain. Or maybe it’s the simple fact that on these platforms, we are the product.

Honestly can’t stop smiling at the love we’ve received for the new @developer.mozilla.org frontend 💜 This was a huge rebuild, and seeing devs notice the details makes it all worth it. Thanks for exploring, sharing, and cheering us on 🙌 More on the way 📈 ICYMI ↓ developer.mozilla.org/

Firefox 142 just dropped, what's new ↓ ✅ Full support for the URL Pattern API ✅ Big DOM wins like Selection.getComposedRanges() and Animation.overallProgress ✅ Updates to WebRTC stats, task scheduling, and WebDriver BiDi ✨ and more... Dive deeper 👇 developer.mozilla.org/en-US/docs/...

Introducing a brand-new frontend for MDN, reengineered from the ground up 🎉 Modern CSS, web components, better typography, new icons, and a new search experience. Everything's been rebuilt with care for usability, performance, and dev needs. Explore 👇 developer.mozilla.org/en-US/blog/...

Search from anywhere. Navigate like never before. 🧭 The new MDN front end comes with a new search modal, refreshed UI, and better typography for docs that feel as good as they read. Take a look 👇 developer.mozilla.org/en-US/blog/...

Illinois is launching a first-of-its-kind legal hotline for LGBTQ+ individuals — Illinois Pride Connect. As the only state in the nation that will provide free legal advice to protect the LGBTQ+ community, we'll help fight ignorance with information and cruelty with compassion.

Gecko: Intent to ship web apps in Firefox for Windows

Football is back! ♥️

Steer HTML’s future! 💡 The State of HTML 2025 survey is live. 35 fresh features on the ballot, from popover UX to native graphics & perf APIs. Early answers(last day!) directly feed Interop 2026 roadmaps. 🛣️ Tag a friend who writes <div> for a living! stateofhtml.com/en-US

it was MDN's 20th birthday this week! 🥳 it's a pleasure and a privilege to work on an open-source project this big and loved. appreciate every one of the 100K+ contributors, millions of readers, partners, and mozilla folk! 🫶 here's the cake we cut! 🎂 developer.mozilla.org/en-US/blog/...

How has MDN helped you? Share your stories.

MDN is 20 years old! 🥳 🙏 A huge thank you to... The devs who read and trust MDN The contributors who improve it Everyone working on the web platform who shares our mission. Here's how we celebrated with the web.dev team! 🧁 developer.mozilla.org/en-US/blog/...

MDN turned 20, and to celebrate, the Chrome team sent us a cake! 🎂 🧁 More than dessert, it’s about open standards. We still remember the cakes from Microsoft during Firefox 2, 3, and 4… and the one we sent them for IE10! Here's ours 👇

to work on something that has a mark on the history of building on the web ✨ @developer.mozilla.org ❤️ screenshot from → deno.com/blog/histor...

docs aren’t just docs anymore, they’re critical infrastructure. 🏗️ After years of pushing for better investment in docs, it’s clear: in an AI + API + MCP world, documentation is part of your production runtime.

someone at whatsapp did not pay their API billing 😂

great product, absolutely shit marketing. I ordered something six months ago, and I get this spam via email and SMS every other day. Who approves this at DaMENSCH? send them back to whatever spammy loan company they came from, and the manager who thinks this is great.

when did notion become so clunky

Definitely the best conference merch I've ever seen!

Guess what? Pranit, Technical Content Developer from Dell, is facilitating a workshop on Technical Writing! 🎉 If you're still trying to get started in technical writing, come join us and learn how to write web docs! 📖 🗓️ Wed, April 30th at 17:00 CET 💬 MDN Discord! Discord link in the next post! 👇

i’ll play cities: skyline today. let’s see how it goes.

Women Who Code is back?????? 😍 @womenwhocode.bsky.social womenwhocode.com

i'm convinced that UPS is entirely incompetent. I got a "We were unable to deliver your package" when I was sitting at home. I've got nowhere to go, I'm sick, bring me my package I paid expedited shipping for.

ever wondered what is the value of OSS? A Harvard study has determined that the OSS services and products worth $4.15B create a value of $8.8T. Firms would need to spend 3.5 times more on software than they currently do if OSS did not exist. 🔗 www.hbs.edu/ris/Publica...

The CFP for @allthingsopen.bsky.social closes Friday. Get those CFPs in peeps! allthingsopen.org/call-for-pap...

i finally hit the stage again after five years! ⭐ nerves aside, it was an exhilarating experience—especially on one of the biggest platforms for open source. loved every moment! you can watch the talk now 👇 youtu.be/ON5ni13i3Rk...

roses are red. violets are blue. #opensource over everything, boo. foundation.mozilla.org/blog/funding...

i adore the contributor spotlight program, it gives me a lot of happiness and gives me a chance to introduce you to our amazing contributors, at MDN! ❤️ this month -- we have Yash, who worked so hard on the SVG content! 🖼️ Read his journey 👇 developer.mozilla.org/en-US/commu...

There's a petition to ban conversion practices (targeting LGBTQIA+ people) in the European Union. We need one million signatures, and we currently have 180,000+. If you live in Europe (even if you don't), spread the word ! 🌈🔥✊ eci.ec.europa.eu/043/public/#...

i'm speaking at @fosdem.bsky.social 🎈 i'll be going over two decades of mdn, how we manage a community at scale. 🗓️ feb 2, 15.20 if you're going to be around at fosdem, come say hi at the Mozilla booth or devroom ❤️ talk details 👇 fosdem.org/2025/schedul...

There were better shows on Netflix when it cost $10 a month

It's 2025 and everything sucks and everyone is job hunting, please enjoy this slowly unfolding thread of tech jobs at places that aren't making the world worse. If you're hiring at not-evil (or even minimally evil) orgs, please reply w your tech jobs too?

Highlighting that my team is hiring. Great work/life balance + lots of choice in technical direction. Best manager I've had in tech. OSS platform that collects speech for a CC0 dataset w 130+ languages. Great gig for language dorks. Happy to answer questions but am not the hiring mgr👋