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  • The two-value syntax of the CSS Display property

    The display CSS property is how we change the formatting context of an element and its children. One of the first things you will learn about CSS is that some elements are block by default, and others are inline. The display property enables switching between these states. With support currently ...

  • Firefox 70 — a bountiful release for all

    Firefox 70 is released today, and includes great new features such as secure password generation with Lockwise and the new Firefox Privacy Protection Report, as well as cool additions for developers. These include DOM mutation breakpoints and inactive CSS rule indicators in the DevTools, several new CSS text properties, two-value ...

  • Quickly Alter Typography with Firefox Font Editor

    Have you ever landed on a web page and wondered what fonts are being used? Have you asked yourself where those fonts come from or why a particular font isn't loading? The font editor in Firefox provides answers and insights, and gives you the ability to make font changes directly, ...

  • Faster Layouts with CSS Grid (and Subgrid!)

    CSS Grid has been available in most major browsers since early 2017, and it makes web layout more powerful than ever before. But complex-looking new syntax (line-names! grid-areas! minmax! fit-content! fr units!) and missing IE11 support can make it scary. Don’t let that stop you. Miriam Suzanne offers some basic ...

  • Developing cross-browser extensions with web-ext 3.2.0

    The web-ext tool was created at Mozilla to help you build browser extensions faster and more easily. Although our first launch focused on support for the desktop Firefox browser, followed by Firefox for Android, our vision was always to support cross-platform development once we shipped Firefox support. With the 3.2.0 ...

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