MDN Web Docs
@developer.mozilla.org
The official MDN Web Docs account, now on Bluesky. We deliver the best web docs around.
Visit → https://mdn.dev
Contribute → https://mdn.dev/community
Visit → https://mdn.dev
Contribute → https://mdn.dev/community
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 👇
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 👇
November 11, 2025 at 9:00 PM
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 👇
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 👇
🧩 Your supply chain is only as strong as its weakest dependency.
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
Supply chain attacks - Security | MDN
A software supply chain consists of all the software and tools used to create and maintain a software product. This includes not only the software developed for the product itself but all the software and tools used in its production.
developer.mozilla.org
November 10, 2025 at 9:00 PM
🧩 Your supply chain is only as strong as its weakest dependency.
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
💡 Want seamless page-to-page animations — no JS required?
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
A beginner-friendly guide to view transitions in CSS | MDN Blog
Learn how to bring smooth, animated navigation to multi-page apps with view transitions. With just one line of CSS, you can enable seamless transitions between pages.
developer.mozilla.org
November 7, 2025 at 4:00 PM
💡 Want seamless page-to-page animations — no JS required?
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
🔔 New changes in default UA styles for in
in
Default styles for h1 elements are changing | MDN Blog
Browsers are starting to roll out changes in default UA styles for nested section headings. This post describes the incoming changes, how to identify if it's an issue on your websites, and hints for conformant and better-structured pages.
developer.mozilla.org
November 7, 2025 at 4:00 AM
🔔 New changes in default UA styles for in
in
MDN is more than just a resource. It's a community of developers, contributors, and learners passionate about web development.
Contribute to,
📚 MDN documentation
🤝 Help other devs
💟 Localize content
📝 Review or write on MDN
Start now 👇
developer.mozilla.org/en-US/commu...
Contribute to,
📚 MDN documentation
🤝 Help other devs
💟 Localize content
📝 Review or write on MDN
Start now 👇
developer.mozilla.org/en-US/commu...
Contribute to MDN
The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.
developer.mozilla.org
November 6, 2025 at 12:00 PM
MDN is more than just a resource. It's a community of developers, contributors, and learners passionate about web development.
Contribute to,
📚 MDN documentation
🤝 Help other devs
💟 Localize content
📝 Review or write on MDN
Start now 👇
developer.mozilla.org/en-US/commu...
Contribute to,
📚 MDN documentation
🤝 Help other devs
💟 Localize content
📝 Review or write on MDN
Start now 👇
developer.mozilla.org/en-US/commu...
Margin? Border? Padding? Content? 💅
The CSS box model is the foundation of layout, and MDN’s interactive exercises help you truly understand how it all fits together.
💡 Practice live in your browser
developer.mozilla.org/en-US/docs/...
The CSS box model is the foundation of layout, and MDN’s interactive exercises help you truly understand how it all fits together.
💡 Practice live in your browser
developer.mozilla.org/en-US/docs/...
Test your skills: The box model - Learn web development | MDN
The aim of this skill test is to help you assess whether you understand the CSS box model.
developer.mozilla.org
November 6, 2025 at 5:00 AM
Margin? Border? Padding? Content? 💅
The CSS box model is the foundation of layout, and MDN’s interactive exercises help you truly understand how it all fits together.
💡 Practice live in your browser
developer.mozilla.org/en-US/docs/...
The CSS box model is the foundation of layout, and MDN’s interactive exercises help you truly understand how it all fits together.
💡 Practice live in your browser
developer.mozilla.org/en-US/docs/...
This is the web you know and build on. 🛠️
A great visual by HeyNina101 from SketechWorld, covering HTML & CSS to TCP & TLS - the core layers that keep everything running.
A great visual by HeyNina101 from SketechWorld, covering HTML & CSS to TCP & TLS - the core layers that keep everything running.
November 5, 2025 at 1:00 PM
This is the web you know and build on. 🛠️
A great visual by HeyNina101 from SketechWorld, covering HTML & CSS to TCP & TLS - the core layers that keep everything running.
A great visual by HeyNina101 from SketechWorld, covering HTML & CSS to TCP & TLS - the core layers that keep everything running.
🧩 Your supply chain is only as strong as its weakest dependency.
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
Supply chain attacks - Security | MDN
A software supply chain consists of all the software and tools used to create and maintain a software product. This includes not only the software developed for the product itself but all the software and tools used in its production.
developer.mozilla.org
November 5, 2025 at 7:00 AM
🧩 Your supply chain is only as strong as its weakest dependency.
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
From securing build tools to verifying external scripts, this new MDN guide by @openwebdocs.org walks you through steps to protect your projects from supply chain attacks.
Read the guide 👇
developer.mozilla.org/en-US/docs/...
✨ One line of CSS. Smooth page transitions. No JavaScript.
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
A beginner-friendly guide to view transitions in CSS | MDN Blog
Learn how to bring smooth, animated navigation to multi-page apps with view transitions. With just one line of CSS, you can enable seamless transitions between pages.
developer.mozilla.org
November 4, 2025 at 9:00 PM
✨ One line of CSS. Smooth page transitions. No JavaScript.
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
Don’t fear the terminal, embrace it! 🫂
Get comfortable with the command line and learn,
✅ How to open your terminal
✅ Common commands like cd, ls, and mkdir
✅ How to create, move, and delete files and folders
Get the cheat sheet! 👇
developer.mozilla.org/en-US/docs/...
Get comfortable with the command line and learn,
✅ How to open your terminal
✅ Common commands like cd, ls, and mkdir
✅ How to create, move, and delete files and folders
Get the cheat sheet! 👇
developer.mozilla.org/en-US/docs/...
Command line crash course - Learn web development | MDN
In your development process, you'll undoubtedly be required to run some commands in the terminal (or on the "command line" — these are effectively the same thing). This article provides an introduction to the terminal, the essential commands you'll need to enter into it, how to chain commands together, and how to add your own command line interface (CLI) tools.
developer.mozilla.org
November 4, 2025 at 4:00 PM
Don’t fear the terminal, embrace it! 🫂
Get comfortable with the command line and learn,
✅ How to open your terminal
✅ Common commands like cd, ls, and mkdir
✅ How to create, move, and delete files and folders
Get the cheat sheet! 👇
developer.mozilla.org/en-US/docs/...
Get comfortable with the command line and learn,
✅ How to open your terminal
✅ Common commands like cd, ls, and mkdir
✅ How to create, move, and delete files and folders
Get the cheat sheet! 👇
developer.mozilla.org/en-US/docs/...
✨ Meet Shrinivass, a Sr Full Stack Engineer from USA, contributing for over a year—improving docs like :has() and DOMContentLoaded.
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
Shrinivass Arunachalam Balasubramanian - Contributor Spotlight | MDN
The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.
developer.mozilla.org
November 3, 2025 at 9:00 PM
✨ Meet Shrinivass, a Sr Full Stack Engineer from USA, contributing for over a year—improving docs like :has() and DOMContentLoaded.
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
Ever seen `__proto__` in JavaScript and thought nothing of it? 💥
You might be opening the door to prototype pollution - a sneaky vulnerability that lets attackers modify built-in objects like `Object.prototype`.
Learn how it works 👇
developer.mozilla.org/en-US/docs/...
You might be opening the door to prototype pollution - a sneaky vulnerability that lets attackers modify built-in objects like `Object.prototype`.
Learn how it works 👇
developer.mozilla.org/en-US/docs/...
JavaScript prototype pollution - Security | MDN
Prototype pollution is a vulnerability where an attacker can add or modify properties on an object's prototype. This means malicious values can unexpectedly appear on objects in your application, often leading to logic errors or additional attacks like cross-site scripting (XSS).
developer.mozilla.org
November 3, 2025 at 11:56 AM
Ever seen `__proto__` in JavaScript and thought nothing of it? 💥
You might be opening the door to prototype pollution - a sneaky vulnerability that lets attackers modify built-in objects like `Object.prototype`.
Learn how it works 👇
developer.mozilla.org/en-US/docs/...
You might be opening the door to prototype pollution - a sneaky vulnerability that lets attackers modify built-in objects like `Object.prototype`.
Learn how it works 👇
developer.mozilla.org/en-US/docs/...
✨ Meet Shrinivass, a Sr Full Stack Engineer from USA, contributing for over a year—improving docs like :has() and DOMContentLoaded.
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
Shrinivass Arunachalam Balasubramanian - Contributor Spotlight | MDN
The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.
developer.mozilla.org
October 30, 2025 at 12:00 PM
✨ Meet Shrinivass, a Sr Full Stack Engineer from USA, contributing for over a year—improving docs like :has() and DOMContentLoaded.
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
He says, “I contribute because it’s mentorship at scale. Each improvement helps thousands of devs.”
Huge thanks! 🙌
developer.mozilla.org/en-US/commu...
✅ Newly Available: CookieChangeEvent
It lets you respond to cookie changes as they happen, using modern event-driven logic in your app or service worker. The event is fired when cookies are added, changed, or deleted.
Try now 👇
developer.mozilla.org/en-US/docs/...
It lets you respond to cookie changes as they happen, using modern event-driven logic in your app or service worker. The event is fired when cookies are added, changed, or deleted.
Try now 👇
developer.mozilla.org/en-US/docs/...
CookieChangeEvent: CookieChangeEvent() constructor - Web APIs | MDN
The CookieChangeEvent() constructor creates a new CookieChangeEvent object
which is the event type of the change event fired at a CookieStore when any cookie changes occur.
This constructor is called by the browser when a change event occurs.
developer.mozilla.org
October 27, 2025 at 9:02 PM
✅ Newly Available: CookieChangeEvent
It lets you respond to cookie changes as they happen, using modern event-driven logic in your app or service worker. The event is fired when cookies are added, changed, or deleted.
Try now 👇
developer.mozilla.org/en-US/docs/...
It lets you respond to cookie changes as they happen, using modern event-driven logic in your app or service worker. The event is fired when cookies are added, changed, or deleted.
Try now 👇
developer.mozilla.org/en-US/docs/...
Using CSS Scroll Snap Events yet? 📜
Triggering JS events whenever snapping occurs can allow you to,
🖲️ Track the scroll position
🔱 Trigger animations
💅 Update UI elements
🍬 Provide feedback
Start creating polished and fluid interactions ✨
developer.mozilla.org/en-US/docs/...
Triggering JS events whenever snapping occurs can allow you to,
🖲️ Track the scroll position
🔱 Trigger animations
💅 Update UI elements
🍬 Provide feedback
Start creating polished and fluid interactions ✨
developer.mozilla.org/en-US/docs/...
Using scroll snap events - CSS: Cascading Style Sheets | MDN
The CSS scroll snap module defines two scroll snap events: scrollsnapchanging and scrollsnapchange. These enable running JavaScript in response to the browser determining that new scroll snap targets are pending and selected, respectively.
developer.mozilla.org
October 27, 2025 at 5:50 PM
Using CSS Scroll Snap Events yet? 📜
Triggering JS events whenever snapping occurs can allow you to,
🖲️ Track the scroll position
🔱 Trigger animations
💅 Update UI elements
🍬 Provide feedback
Start creating polished and fluid interactions ✨
developer.mozilla.org/en-US/docs/...
Triggering JS events whenever snapping occurs can allow you to,
🖲️ Track the scroll position
🔱 Trigger animations
💅 Update UI elements
🍬 Provide feedback
Start creating polished and fluid interactions ✨
developer.mozilla.org/en-US/docs/...
Newly Available since Firefox 140 ✅
🍪 CookieStore API offers a modern, promise-based way to read, write, update, and delete cookies, all without parsing strings manually. It brings,
✅ Async operations
✅ Structured data
✅ Service worker support
developer.mozilla.org/en-US/docs/...
🍪 CookieStore API offers a modern, promise-based way to read, write, update, and delete cookies, all without parsing strings manually. It brings,
✅ Async operations
✅ Structured data
✅ Service worker support
developer.mozilla.org/en-US/docs/...
CookieStore - Web APIs | MDN
The CookieStore interface of the Cookie Store API provides methods for getting and setting cookies asynchronously from either a page or a service worker.
developer.mozilla.org
October 24, 2025 at 3:00 PM
Newly Available since Firefox 140 ✅
🍪 CookieStore API offers a modern, promise-based way to read, write, update, and delete cookies, all without parsing strings manually. It brings,
✅ Async operations
✅ Structured data
✅ Service worker support
developer.mozilla.org/en-US/docs/...
🍪 CookieStore API offers a modern, promise-based way to read, write, update, and delete cookies, all without parsing strings manually. It brings,
✅ Async operations
✅ Structured data
✅ Service worker support
developer.mozilla.org/en-US/docs/...
✨ One line of CSS. Smooth page transitions. No JavaScript.
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
A beginner-friendly guide to view transitions in CSS | MDN Blog
Learn how to bring smooth, animated navigation to multi-page apps with view transitions. With just one line of CSS, you can enable seamless transitions between pages.
developer.mozilla.org
October 23, 2025 at 11:00 AM
✨ One line of CSS. Smooth page transitions. No JavaScript.
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
```
@view-transition {
navigation: auto;
}
```
The 🆕 CSS View Transitions bring native animations to multi-page apps, no SPA setup needed!
Explore now 👇
developer.mozilla.org/en-US/blog/...
Need your numbers to line up? Or prefer old-school serif-style numerals?
CSS has a property for that: font-variant-numeric
// font-variant-numeric: tabular-nums;
✅ Tabular vs proportional
✅ Lining vs oldstyle
✅ Even supports slashed zero
Read more 👇
developer.mozilla.org/en-US/docs/...
CSS has a property for that: font-variant-numeric
// font-variant-numeric: tabular-nums;
✅ Tabular vs proportional
✅ Lining vs oldstyle
✅ Even supports slashed zero
Read more 👇
developer.mozilla.org/en-US/docs/...
font-variant-numeric - CSS | MDN
The font-variant-numeric CSS property controls the usage of alternate glyphs for numbers, fractions, and ordinal markers.
developer.mozilla.org
October 22, 2025 at 12:00 PM
Need your numbers to line up? Or prefer old-school serif-style numerals?
CSS has a property for that: font-variant-numeric
// font-variant-numeric: tabular-nums;
✅ Tabular vs proportional
✅ Lining vs oldstyle
✅ Even supports slashed zero
Read more 👇
developer.mozilla.org/en-US/docs/...
CSS has a property for that: font-variant-numeric
// font-variant-numeric: tabular-nums;
✅ Tabular vs proportional
✅ Lining vs oldstyle
✅ Even supports slashed zero
Read more 👇
developer.mozilla.org/en-US/docs/...
ICYMI: Firefox 144 is out! 📣
What's new for devs:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪)
Read more 👇
developer.mozilla.org/en-US/docs/...
What's new for devs:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪)
Read more 👇
developer.mozilla.org/en-US/docs/...
Firefox 144 for developers - Mozilla | MDN
This article provides information about the changes in Firefox 144 that affect developers.
Firefox 144 was released on October 14, 2025.
developer.mozilla.org
October 21, 2025 at 3:00 PM
ICYMI: Firefox 144 is out! 📣
What's new for devs:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪)
Read more 👇
developer.mozilla.org/en-US/docs/...
What's new for devs:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪)
Read more 👇
developer.mozilla.org/en-US/docs/...
💡 Want seamless page-to-page animations — no JS required?
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
A beginner-friendly guide to view transitions in CSS | MDN Blog
Learn how to bring smooth, animated navigation to multi-page apps with view transitions. With just one line of CSS, you can enable seamless transitions between pages.
developer.mozilla.org
October 20, 2025 at 8:00 PM
💡 Want seamless page-to-page animations — no JS required?
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
The new CSS view-transition at-rule makes it possible!
✅ Works in Chrome, Edge, Safari
🦊 Coming soon to Firefox 144
💫 Perfect for progressive enhancement
Get started 👇
developer.mozilla.org/en-US/blog/...
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 exploring 👇
developer.mozilla.org/en-US/blog/...
The NEW Temporal API brings,
🌍 Easily handle time zones
📆 Precise date math
🕒 Parse ISO strings without errors
⌛ Durations, date ranges, and more.
Start exploring 👇
developer.mozilla.org/en-US/blog/...
JavaScript Temporal is coming | MDN Blog
A new way to handle dates and times is being added to JavaScript. Let's take a look at Temporal, what problems it solves, the current state, and what you'll find in the new documentation about it on MDN.
developer.mozilla.org
October 17, 2025 at 3:00 PM
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 exploring 👇
developer.mozilla.org/en-US/blog/...
The NEW Temporal API brings,
🌍 Easily handle time zones
📆 Precise date math
🕒 Parse ISO strings without errors
⌛ Durations, date ranges, and more.
Start exploring 👇
developer.mozilla.org/en-US/blog/...
📣 Firefox 144 is out!
What's new for developers:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪exp.)
Read more 👇
developer.mozilla.org/en-US/docs/...
What's new for developers:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪exp.)
Read more 👇
developer.mozilla.org/en-US/docs/...
Firefox 144 for developers - Mozilla | MDN
This article provides information about the changes in Firefox 144 that affect developers.
Firefox 144 was released on October 14, 2025.
developer.mozilla.org
October 17, 2025 at 3:00 AM
📣 Firefox 144 is out!
What's new for developers:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪exp.)
Read more 👇
developer.mozilla.org/en-US/docs/...
What's new for developers:
🧩 View Transition API for SPAs
⚙️ New Map/WeakMap methods (getOrInsert)
🧱 Element.moveBefore()
📱 ScreenOrientation.lock()
🕐 Built-in time picker for (🧪exp.)
Read more 👇
developer.mozilla.org/en-US/docs/...
✨ Imagine if your site could animate smoothly between pages — without a reload.
That’s now possible with CSS View Transitions, bringing SPA-like animations to multi-page apps!
A beginner-friendly guide by Yash Raj Bharti ↓
developer.mozilla.org/en-US/blog/...
That’s now possible with CSS View Transitions, bringing SPA-like animations to multi-page apps!
A beginner-friendly guide by Yash Raj Bharti ↓
developer.mozilla.org/en-US/blog/...
A beginner-friendly guide to view transitions in CSS | MDN Blog
Learn how to bring smooth, animated navigation to multi-page apps with view transitions. With just one line of CSS, you can enable seamless transitions between pages.
developer.mozilla.org
October 16, 2025 at 5:12 PM
✨ Imagine if your site could animate smoothly between pages — without a reload.
That’s now possible with CSS View Transitions, bringing SPA-like animations to multi-page apps!
A beginner-friendly guide by Yash Raj Bharti ↓
developer.mozilla.org/en-US/blog/...
That’s now possible with CSS View Transitions, bringing SPA-like animations to multi-page apps!
A beginner-friendly guide by Yash Raj Bharti ↓
developer.mozilla.org/en-US/blog/...
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survey.alchemer.com
October 16, 2025 at 1:30 PM
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Reposted by MDN Web Docs
I dug into progressive image rendering and found a bunch of common assumptions aren't quite true.
➡️ JPEG & WebP progressive-renders worse in Safari
➡️ AVIF _does_ support progressive
➡️ But JPEG XL in Safari doesn't
➡️ JPEG XL decodes much slower than AVIF
⬇️ and more
jakearchibald.com/2025/present...
➡️ JPEG & WebP progressive-renders worse in Safari
➡️ AVIF _does_ support progressive
➡️ But JPEG XL in Safari doesn't
➡️ JPEG XL decodes much slower than AVIF
⬇️ and more
jakearchibald.com/2025/present...
The present and potential future of progressive image rendering
Exploring progressive image rendering across JPEG, PNG, WebP, AVIF, and JPEG XL.
jakearchibald.com
October 16, 2025 at 10:16 AM
I dug into progressive image rendering and found a bunch of common assumptions aren't quite true.
➡️ JPEG & WebP progressive-renders worse in Safari
➡️ AVIF _does_ support progressive
➡️ But JPEG XL in Safari doesn't
➡️ JPEG XL decodes much slower than AVIF
⬇️ and more
jakearchibald.com/2025/present...
➡️ JPEG & WebP progressive-renders worse in Safari
➡️ AVIF _does_ support progressive
➡️ But JPEG XL in Safari doesn't
➡️ JPEG XL decodes much slower than AVIF
⬇️ and more
jakearchibald.com/2025/present...