Chrome 154 beta

Rachel Andrew

Published: September 2, 2026

Unless otherwise noted, the following changes apply to the newest Chrome beta channel release for Android, ChromeOS, Linux, macOS, and Windows. Learn more about these features by using the provided links or by visiting ChromeStatus.com. Chrome 154 is in beta as of September 2, 2026. You can download the latest beta version from Google.com for desktop or from Google Play Store on Android.

CSS and UI

CSS scroll-marker-group modes

The scroll-marker-group property is enhanced to support the following modes:

  • links: The generated ::scroll-marker-group operates in links mode, functioning like a navigation list. This is the default mode if omitted.
  • tabs: The generated ::scroll-marker-group operates in tabs mode, functioning like a tablist.

Each mode changes the focus order and accessibility behavior of ::scroll-marker-group and ::scroll-marker, following WAI-ARIA patterns:

  • Links mode (default): Mimics standard navigation landmarks combined with fragment anchors. The ::scroll-marker-group takes on the navigation role, and ::scroll-marker elements take on the link role. All ::scroll-marker elements are sequential tab stops. When a link marker is activated, focus moves to the target element.
  • Tabs mode: Replicates the tabs pattern and serves as the foundation for tabbed carousels. The ::scroll-marker-group is assigned the tablist role, ::scroll-marker elements act as tab roles, and originating elements get the tabpanel role. Only the active ::scroll-marker acts as a tab stop, using arrow keys to navigate between markers. Content from inactive tabs is hidden from the accessibility tree.

CSS text-decoration-inset

The text-decoration-inset CSS property controls how far underlines, overlines, and line-through decorations are inset from or extended beyond text run edges. It supports auto, length, and percentage values, including one-value and two-value syntax for setting start and end offsets. This lets developers adjust decoration spacing and create reveal effects with native text decorations instead of background gradients or additional elements.

CSS text-decoration-skip-spaces

The text-decoration-skip-spaces CSS property controls whether text decoration lines (such as underlines, overlines, and line-throughs) skip over whitespace characters. This lets you prevent decorations from being drawn under spaces.

Expose CSSStyleValue hierarchy to Worker contexts

The CSS Typed OM specification exposes the CSSStyleValue hierarchy to worker global scopes ([Exposed=(Window, Worker, PaintWorklet, LayoutWorklet)]), but Blink previously only exposed CSSStyleValue, CSSKeywordValue, CSSNumericValue, CSSUnitValue, and CSSUnparsedValue to Window and worklets. As a result, these constructors were undefined in Worker contexts. Chrome 154 exposes these constructors in workers, aligning with the specification and other browser engines.

FontFace width attribute and font-width descriptor

Exposes the width attribute on FontFace and the @font-face font-width descriptor as aliases for stretch and font-stretch. This aligns Chromium with the updated CSS Font Loading and CSS Fonts 4 specifications. You can inspect or initialize font face widths using FontFace.width and CSS font-width interchangeably with stretch and font-stretch.

Light dismiss improvements for popovers and dialogs

Improves and simplifies the light dismiss behavior for popovers and dialogs. Light dismiss is the behavior where clicking outside of a popover or dialog closes it. These improvements ensure that scrolling gestures on touchscreens and right-clicks no longer trigger light dismiss.

The browser now uses click events to trigger light dismiss instead of a combination of pointerdown and pointerup events.

Responsively-sized <iframe>

Lets sites opt into iframes with responsive sizing. This sizes the <iframe> element in the parent document to the iframe document's layout overflow sizing, avoiding scrolling in the child document.

JavaScript

Iterator includes

A TC39 proposal that adds an includes() method to iterators, letting you check whether an iterator yields a given value, similar to Array.prototype.includes().

Web APIs

Add options bag to WebSocket constructor

Adds support for passing an options dictionary (WebSocketInit) as the second argument to the WebSocket constructor. The options dictionary supports a protocols option, letting you specify subprotocols (mirroring the existing protocols argument), and serves as an extension point for future options.

Previously, this was written as:

const socket = new WebSocket("wss://example.com:8080", "soap");

With this change, it can also be written as:

const socket = new WebSocket("wss://example.com:8080", { protocols: "soap" });

Algorithm updates in WebCrypto

Adds post-quantum cryptography and a symmetric AEAD algorithm to the set of cryptographic algorithms available in the Web Cryptography API. This gives you access to browser-provided implementations of quantum-resistant cryptographic algorithms standardized by NIST:

  • ML-KEM (768, 1024)
  • ML-DSA (44, 65, 87)
  • ChaCha20-Poly1305
  • X-Wing

CORS enforcement for Background Fetch

The Background Fetch API now enforces Cross-Origin Resource Sharing (CORS).

This update aligns Chromium's implementation with the intent of the Background Fetch specification. This ensures that Background Fetch requests are subject to the same security policies, such as Local Network Access checks, preventing sites from bypassing CORS and other security policy checks by using Background Fetch instead of regular Fetch.

Fetch API: Forward reason from AbortController to fetch Response

Exposes the abort reason, if one is provided, to the methods of the Response object and its ReadableStream, rather than only the fetch promise. This aligns Chrome with the standard, surfacing the developer-supplied abort reason everywhere intended.

Local Network Access restrictions for Background Fetch

Background Fetch requests require that the service worker's origin has the necessary Local Network Access (LNA) permission to send requests to local or loopback servers.

This aligns Chromium's implementation with the intent of the Background Fetch specification, which states that requests go through the Fetch specification and have the same security policies applied to them. This prevents sites from bypassing LNA checks by using Background Fetch instead of regular Fetch.

For enterprises, you can use existing LNA enterprise policies in the same way as for regular Fetch API requests from service workers:

Renewed HTML insertion and streaming methods

Exposes multiple HTML setting methods that provide a coherent approach for dynamically inserting markup into an existing document:

  • Positional methods (before(), after(), append(), prepend(), and replaceWith()) that take HTML as an argument, replacing insertAdjacentHTML().
  • Streaming methods (streamAppendHTML(), streamAppendHTMLUnsafe(), and related methods) which return a WritableStream.
  • Passing {runScripts} as part of SetHTMLUnsafeOptions, matching createContextualFragment behavior.
  • Supporting createParserOptions in Trusted Types, letting Trusted Types override the scripting mode and sanitizer.

Secure Payment Confirmation: Locale validation

Updates the Secure Payment Confirmation locale data field to return a NotSupportedError DOMException if none of the language tags provided in the field match the language used by the Secure Payment Confirmation dialog. If the field is not set or is empty, this validation is skipped.

This helps match the language of the data supplied to Secure Payment Confirmation with the dialog.

Support targetAddressSpace option for WebSockets

Adds support for passing a targetAddressSpace option in the WebSocket constructor. This lets you specify that a WebSocket connection to a public hostname should be treated as going to a "local" or "loopback" destination, matching existing support in the Fetch API. The main use case is to bypass mixed content restrictions when connecting to local servers that don't support HTTPS, because Local Network Access permissions require a secure context.

For example, a public site that connects to a local server can use a hostname instead of manual configuration of the exact private IP address:

const ws = new WebSocket("ws://local-server.example", { targetAddressSpace: "local" });

This flags the WebSocket connection as going to a local address, bypassing mixed content blocking when run in a secure context. The user must grant the site the local network permission for the WebSocket connection to succeed, and the hostname must resolve to a local IP address (otherwise it is blocked).

This feature builds on the options dictionary added to the WebSocket constructor.

WebGPU: WGSL fragment depth

Adds the ability to provide a less or greater modifier to @builtin(frag_depth) in WGSL.

Using @builtin(frag_depth) without modifiers can introduce a performance penalty by disabling early-Z optimizations on a draw call. The new modifiers allow explicit setting of the buffer mode, enabling early-Z optimizations to be applied.

Window Shape API

The Window Shape API lets allowlisted Isolated Web Apps on ChromeOS have a customized window shape. By enabling non-rectangular and non-contiguous window layouts, developers can implement experiences such as widgets, floating panels, and overlays that match the appearance of native applications. The window.setShape() method requires the window to be in unframed display mode and requires the window-management permission.

Administrators can manage this feature with existing policies for window management:

New origin trials

In Chrome 154, you can opt into the following new origin trials.

Private Verification Tokens

Private Verification Tokens (PVT) is a low-entropy mechanism that lets websites transfer the trust that users have established in regular browsing into private browsing mode, reducing user friction from CAPTCHAs and challenges. PVTs are issued during a regular browsing session and redeemed in private browsing mode.