New to the web platform in October

Discover some of the interesting features that have landed in stable and beta web browsers during October 2024.

Rachel Andrew

Stable browser releases

In October 2024, Firefox 131, Firefox 132, Safari 18.1, and Chrome 130 became stable. This post looks at the new features added to the web platform.

Synchronous iterator helpers

Firefox 131 adds support for synchronous iterator helpers. For example, Iterator.prototype.forEach() and Iterator.prototype.map(). These helpers allow array-like operations on iterators without creating intermediate array objects, including very large data sets where creating an intermediate array wouldn't be possible.

Browser Support

  • Chrome: 122.
  • Edge: 122.
  • Firefox: 131.
  • Safari: not supported.

Source

Text fragments

Also in Firefox 131 is support for text fragments, along with the CSS ::target-text pseudo-element.

Browser Support

  • Chrome: 89.
  • Edge: 89.
  • Firefox: 131.
  • Safari Technology Preview: supported.

Source

Cookies Having Independent Partitioned State (CHIPS)

Firefox 131 includes CHIPS letting you opt cookies into partitioned storage using the partitioned directive of the Set-Cookie HTTP header.

Browser Support

  • Chrome: 114.
  • Edge: 114.
  • Firefox: 131.
  • Safari: not supported.

Source

Media updates

In the second Firefox release during October are a set of media features that all join Baseline Newly available. Firefox 132 includes the requestVideoFrameCallback() and cancelVideoFrameCallback() methods of HTMLVideoElement.

Browser Support

  • Chrome: 83.
  • Edge: 83.
  • Firefox: 132.
  • Safari: 15.4.

Source

Also included is the MediaStreamTrack.getCapabilities() method.

Browser Support

  • Chrome: 59.
  • Edge: 12.
  • Firefox: 132.
  • Safari: 11.

Source

fetchPriority

The Fetch Priority API indicates the relative priority of resources to the browser. It's supported from Firefox 132, which means that this helpful API is now Baseline Newly available.

Learn more in Optimize resource loading with the Fetch Priority API.

Browser Support

  • Chrome: 102.
  • Edge: 102.
  • Firefox: 132.
  • Safari: 17.2.

Source

Full box-decoration-break support

Chrome 130 includes full, unprefixed support for the CSS box-decoration-break property. This includes the value of clone for block and inline fragmentation.

Browser Support

  • Chrome: 130.
  • Edge: 130.
  • Firefox: 32.
  • Safari: 7.

Source

Learn more about the property in The box-decoration-break property in Chrome 130.

The nested declarations rule

Chrome 130 and Firefox 132 support CSS Nested Declarations, this means that nested CSS is correctly parsed as explained in CSS nesting improves with CSSNestedDeclarations.

Browser Support

  • Chrome: 130.
  • Edge: 130.
  • Firefox: 132.
  • Safari: not supported.

The Web Serial connected attribute and RFCOMM connection events

Chrome 130 adds a boolean SerialPort.connected attribute. The attribute returns true if the serial port is logically connected.

With this feature, Bluetooth RFCOMM serial ports dispatch these events when the port becomes logically connected or disconnected.

This feature is intended to allow applications to detect when a Bluetooth RFCOMM serial port is available without opening the port.

Learn more in Bluetooth RFCOMM updates in Web Serial.

Browser Support

  • Chrome: 130.
  • Edge: not supported.
  • Firefox: not supported.
  • Safari: not supported.

Accessibility fixes in Safari

The Safari 18.1 release comes quickly after Safari 18, and fixes a number of accessibility issues, notably with display: contents.

Beta browser releases

Beta browser versions give you a preview of things that will be in the next stable version of the browser. It's a great time to test new features, or removals, that could impact your site before the world gets that release. New betas are Firefox 133 and Chrome 131. These releases bring many great features to the platform. Check out the release notes for all of the details. Here are just a few highlights.

Firefox 133 supports the ImageDecoder, ImageTrackList, and ImageTrack interfaces of the WebCodecs API, enabling the decoding images from the main and worker threads.

Firefox 133 also supports WorkerNavigator.permissions.

Chrome 131 includes CSS highlight inheritance, where the CSS highlight pseudo-classes, such as ::selection and ::highlight, inherit their properties through the pseudo highlight chain, rather than the element chain. The result is a more intuitive model for inheritance of properties in highlights.

Also in Chrome 131 is support for CSS paged media @page margin boxes, so you can provide custom headers and footers when printing from the web.