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  • Firefox’s New WebSocket Inspector

    The Firefox DevTools team and our contributors were hard at work over the summer, getting Firefox 70 jam-packed with improvements. We are especially excited about our new WebSocket inspection feature. To use the inspector now, download Firefox Developer Edition, and open the DevTools’ Network panel to find the Messages tab. ...

  • The Mozilla Developer Roadshow Talks: Firefox, WebAssembly, CSS, WebXR and More

    The Mozilla Developer Roadshow program launched in 2017 with the goal of bringing expert speakers and web technology updates to local communities through free events and partnerships. Check out the video playlist from our summer tour, with talks on topics like Mixed Reality, WebAssembly, modern CSS, and more. Or register ...

  • Why is CSS So Weird?

    CSS is the design language of the web — one of three core web languages — but it also seems to be the most contentious and often perplexing. It's too easy and too hard, too fragile and too resilient. Love it or hate it, CSS is weird: not quite markup, ...

  • Video Shorts from Mozilla Developer

    Today we’re launching a new video channel, with a selection of shorts to kick things off. Get started with an intro to Dark Mode on the web, by Deja Hodge. Then, Jen Simmons shows us how to access a handy third-panel in the Firefox Developer Tools. Miriam Suzanne has a ...

  • WebHint in Firefox DevTools: Improve Compatibility, Accessibility and more

    Creating experiences that look and work great across different browsers is one of the biggest challenges on the web. It can also be the most rewarding part, as it gets your app to as many users as possible. Testing legacy browsers late in the development process can break a feature ...

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