A photo of my face against a blue background.I'm Patrick, a product manager on the Edge team at Microsoft. I do developer relations, and work on a wide range of web platform technologies and tools. Previously, I worked at Mozilla, on the Firefox DevTools team.
I'm part of the Open Web Docs governing committee and a co-chair of the W3C WebDX community group. I also run DevTools Tips.

I have 20+ years of working experience with the web and have worked as a designer, web developer, software engineer, browser engineer, engineering manager, and product manager.

To get in touch, use the links to my social networks at the bottom of this page, or email me: patrickbrosset at gmail dot com.

AI agents and the web - A proposal to keep developers in the loop

WebMCP is an early proposal that allows web developers to take control of how AI agents use their web pages on behalf of users. In this post, I'm providing a short introduction of the proposal, together with a demo. I'm also calling for feedback! If this sounds interesting, please read on and let me know what you think.

A hand-drawn diagram of the WebMCP proposal, showing a user interacting with a webpage in a browser. The user interacts with the page in two ways. One way is directly, as normal, using the browser UI. The other way is through an an AI agent which communicates with the page by using an embedded MCP server in the browser.

Brick by brick: Help us build CSS Masonry

We're working on implementing CSS Masonry in Chromium and are super excited to announce that it's now ready for developer trial. In this blog post, you'll learn about the syntax that's available for you to try, and get inspired by a bunch of examples.

A CSS Masonry layout example, showing a photo gallery where the title spans multiple columns.

The Gap Strikes Back: Now Stylable

Four years go, I wrote about the gap property and a workaround to style it. Today, I'm back to show you how we'll soon have a few simple CSS properties that make it easy, yet also flexible without any fuss.

Abstract illustration

CSS alignment in block layouts

Testing the align-* and justify-* CSS properties in a block layout. View the source code of that page to learn more.

A blue square inside a gray square

Navigating the web platform

A cheatsheet of sorts, to help you navigate the intricacies of the web platform. How to keep track of what's new? How to influence what's coming next?

Screenshot of the cheatsheet.

web-features and Baseline (AC 2025)

A short talk at the W3C AC meeting in April 2025, to update the AC on the web-features project and Baseline. Video, slides.

W3C AC 2025 logo.

web-features and Baseline - We're feature complete! What's next? (W3C Breakouts Day)

The WebDX Community Group has done a lot of work in 2024 to increase the coverage of its web-features data. Now that the data roughly covers the entire web platform feature set, let's review the work done so far, the use cases that web-features, and Baseline, have unlocked, and let's open it up for discussion on the next important questions to tackle.
Slides

W3C Breakouts Day 2025 logo.