New Features

Chrome 128
Stable release date: August 20th, 2024

Unless otherwise noted, the following changes apply to Chrome 128 stable channel release for Android, ChromeOS, Linux, macOS, and Windows.

CSS
CSS ruby-align property
There are multiple ways to align characters when the length of ruby annotations and the base characters don't match, and the ruby-align property lets you choose the one that works best for your design. The property takes one of the following keyword values:

• space-around
• space-between
• start
• center

Line-breakable ruby
Makes line-breaks possible within elements with display: ruby.
Previously a single pair of a ruby-base and a ruby-text was not line-breakable, and would be pushed to the next line if the current line had not enough space for the entire pair. Now each of the ruby-base and the ruby-text can be split into multiple lines.

Minimum size of <option> within <select> drop-down
The WCAG accessibility guidelines specify that the size of pointer inputs must be at least 24 by 24 CSS pixels. This change makes the <option> element within the <select> drop-down meet this height requirement.

Standardized CSS zoom property
Updates the existing implementation of the previously non-standard CSS zoom property to align with the new standard. This changes various JavaScript APIs to align with the spec, changes zoom to apply to iframe content documents, and changes it to apply to all inherited length properties (previously it only changed the inherited font-size).

Web APIs
Additions to Attribution Reporting
Chrome 128 includes two additional features for Attribution Reporting. There are changes to source-destination-limit logic, with the aim of reducing the rate of transmission loss. Flexible contributions filtering will improve API report batching capabilities.

document.caretPositionFromPoint
Returns the current caret position from a given screen point in the form of a CaretPosition object representing the caret position indicating current text insertion point including the containing DOM node, caret's character offset, and the client rectangle of caret range. This feature also supports getting the CaretPosition inside Shadow DOM.

Web Share API on macOS
The API enables web developers to build share buttons that display the same system share dialog boxes used by mobile applications. This previously shipped on Android, Windows, and ChromeOS, and is now also coming to macOS.

Media
AudioContext.onerror
AudioContext creation and audio rendering errors are now reported to web applications with a callback assigned to AudioContext.onerror.

PointerEvent.deviceProperties for multi-pen inking
Currently, developers have no way to distinguish between two individual pens on an ink-enabled digitizer. The existing PointerEvent.id attribute is implemented in different ways and does not always persist for each ink stroke or interaction with the screen.

This change provides a secure and reliable way to identify individual pen (pointers) interacting with the screen to set specific colors or pen shapes for each device interacting with the digitizer. It extends the PointerEvent interface to include a new attribute, deviceProperties. This contains the attribute uniqueId, that represents a session-persistent, document isolated, unique identifier that a developer can reliably use to identify individual pens interacting with the page.

SkipAd media session action
Supports the SkipAd media session action. This action lets browsers show a button in the system media controls or in the Picture-in-Picture window.

Privacy
Cross-site ancestor chain bit for CookiePartitionKey of partitioned cookies
Chrome 128 adds a cross-site ancestor bit to the key ring of the partitioned cookie's CookiePartitionKey. This change unifies the partition key with the partition key values used in storage partitioning and adds protection against clickjacking attacks by preventing cross-site embedded frames from having access to the top-level-site's partitioned cookies.

Private Aggregation API: client-side contribution merging
Modifies the Private Aggregation API to merge histogram contributions with the same bucket and filtering ID before embedding in the aggregatable report's encrypted payload.

Private Aggregation imposes a limit on the number of contributions that can be embedded in a single aggregatable report, with any additional contributions being dropped. By merging contributions where possible, we can get additional utility out of the limit. Note that, ignoring the dropping of excess contributions, merging these sorts of contributions shouldn't have any impact on the final summary reports.

JavaScript
Promise.try
Promise.try is a TC39 proposal for a new static method. Promise.try(f) is shorthand for new Promise(resolve =&gt; resolve(f())).

WebAuthn hints
The new hints parameter in WebAuthn requests lets sites provide guidance to browsers to guide their UI. The canonical use case is enterprises that know their internal sites use only security keys and want to be able to communicate so that browsers focus the UI on that case.
Hints also resolve a tension where the current authenticatorAttachment parameter is strict: setting it to platform excludes all cross-platform options.

Write image/svg+xml content in UTF-8 format on Windows
Switch to UTF-8 on Windows while writing image/svg+xml format to the clipboard. HTML format already uses UTF-* on Windows and this will allow copying and pasting SVG images from the clipboard.
On all other supported platforms, image/svg+xml is serialized into UTF-8 before it gets written to the clipboard.

New origin trials
Digital Credentials API
Websites can request credentials from mobile wallet apps through a variety of mechanisms today, for example custom URL handlers and QR code scanning. This feature lets sites request identity information from digital credentials inside wallets using Android's IdentityCredential CredMan system. It's extensible to support multiple credential formats (for example, ISO mDoc and W3C verifiable credential) and allows multiple wallet apps to be used. The API also includes mechanisms to reduce the risk of ecosystem-scale abuse of sensitive identity information.

FedCM multiple identity providers in single get() call
Allows FedCM to show multiple identity providers in the same dialog. This gives developers a convenient way to present all supported identity providers to users. We are planning to first tackle the case of having all providers in the same get() call.

Disable standardized CSS zoom
The implementation of the previously non-standard CSS zoom property has been updated to align with the new standard. This changes various JavaScript APIs to align with the specification, changes zoom to apply to iframe content documents, and changes it to apply to all inherited length properties where previously it only changed the inherited font-size.

WebGPU Subgroups experimentation
Adds subgroup functionality to WebGPU. Subgroup operations perform SIMT operations to provide efficient communication and data sharing among groups of invocations. These operations can be used to accelerate applications by reducing memory overheads incurred by inter-invocation communication.