What's New in Chrome 143 for Developers

Web Development

Discover the latest developer features in Chrome 143, including anchored fallback container queries, side-relative background-position, and the font-language-override CSS property.

By Rachel Andrew Published: December 2, 2025

Chrome 143 is now rolling out, bringing a suite of new features designed to enhance web development. This post highlights some of the key updates from this release. For a comprehensive overview, please refer to the full Chrome 143 release notes.

Highlights from this release:

  • Style descendants of anchor-positioned elements with anchored fallback container queries.
  • Position CSS background images relative to one of the edges using longhands.
  • Override the system language for glyph substitution with font-language-override.

CSS Anchored Fallback Container Queries

Chrome 143 introduces @container anchored(fallback), a powerful new capability to style descendants of anchor-positioned elements. This styling is contingent on which position-try-fallbacks rule is applied. Such queries are invaluable for styling an anchored element's tether or its animations, dynamically adjusting based on how the anchor and the anchored element are positioned relative to each other.

Side-relative Syntax for background-position-x/y Longhands

Developers can now define a background image's position relative to one of its edges using new longhand properties for background-position. This enhancement provides more precise control over background image placement. For example:

.element {
  background-image: url(flower.gif);
  background-repeat: no-repeat;
  background-position-x: left 30px;
  background-position-y: bottom 20px;
}

This implementation marks the feature as "Baseline Newly available," indicating its stable and widespread readiness for use.

Implement the font-language-override CSS Property

Chrome 143 also introduces support for the font-language-override CSS property. This property empowers developers to override the system language used for OpenType glyph substitution by specifying a four-character language tag directly in CSS. This capability offers fine-grained typographic control, proving particularly useful for multilingual content or when working with fonts that include language-specific glyph variants.

Further Reading

This article covers only the key highlights. For additional changes and details in Chrome 143, please check the following links:

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We'll be back to tell you what's new in Chrome as soon as Chrome 144 is released!