Chrome 155 Release Notes

Enable web applications to maximize, minimize, and restore their windows, control whether the window can be resized, and introspect the corresponding window state.

The Window Management permission is required for new JS API controls (window.maximize()/minimize()/restore()/setResizable(bool)). The new CSS media features display-state and resizable are not gated behind a permission as they can follow the non-AWC API toggled states as well.

This feature is an enhancement of the Window Management API: https://chromestatus.com/feature/5252960583942144

Triggers a request for the browser to install a web app, given a manifest URL and optional manifest ID. The navigator.install() method enables cross-origin web app installation and provides a better developer experience than handling beforeinstallprompt events. Enterprises can control this in two ways - (1) Enterprise policy, WebAppInstallByUserEnabled, can disable user web app installs broadly, including installs initiated via navigator.install() and <install>. Or (2) Permissions Policy, web-app-installation, can allow or disallow use of this feature on origins the enterprise controls (for example, internal sites/iframes).

Triggers a request for the browser to install a web app, given a manifest URL and optional manifest ID. The <install> element enables cross-origin web app installation without JavaScript and provides a better developer experience than handling beforeinstallprompt events. Enterprises can control this in two ways - (1) Enterprise policy, WebAppInstallByUserEnabled, can disable user web app installs broadly, including installs initiated via navigator.install() and <install>. Or (2) Permissions Policy, web-app-installation, can allow or disallow use of this feature on origins the enterprise controls (for example, internal sites/iframes).

The CSS symbols() function lets authors define a counter style inline instead of first declaring a named @counter-style at-rule. It builds an anonymous counter style from a list of string symbols plus an optional counting system (cyclic, numeric, alphabetic, symbolic, or fixed), and is accepted as the counter style in list-style-type, the list-style shorthand, and counter() / counters().

Implements the CSS corner shorthand and per-corner sub-shorthands (corner-top-left, corner-top-right, corner-bottom-left, corner-bottom-right) as well as physical (corner-top, corner-bottom) and logical (corner-block-start, corner-block-end, etc.) edge shorthands. These allow setting both border-radius and corner-shape for individual corners in a single declaration. Additionally, corners is retained as a compat alias for the corner shorthand.

sampler: https://static.januschka.com/i-425897047/

CL: https://chromium-review.googlesource.com/c/chromium/src/+/7747994

The random() function brings generative randomness to CSS, allowing web authors to generate a random numeric value within a specified range.

For example, web authors can use random() to scatter elements randomly within their container: .dot { /* Position each dot randomly */ position: absolute; top: random(0%, 100%); left: random(0%, 100%); }

This feature also includes caching controls. By default, each random() function resolves to a new, distinct value. Web authors can override this default by passing a <random-key> value as the function's first argument to control how random values are shared across properties and elements.

The margin-trim CSS property may be used to omit margins before or after the first or last child of a container. This is supported on regular block containers and multicol containers.

This is somewhat similar to the effect caused by the margin quirk that is applied to P, H1, H2... elements inside BODY and table cell elements (in quirks mode), but more powerful, generic, and expressive.

Note: A previous version of the spec also applied this for flex and grid containers, but this has been removed.

This Web Platform feature enables issuing websites (e.g., a university, government agency, or bank) to securely initiate the provisioning (issuance) process of digital credentials directly into a user's mobile wallet application. On Android, this capability leverages the Android IdentityCredential CredMan system (Credential Manager). On Desktop, it leverages cross-device approaches using the CTAP protocol similar to Digital Credentials presentation.

Add srgb-linear and display-p3-linear color spaces (as defined by CSS) to PredefinedColorSpace for use with canvases.

Enterprise admins can create File download Chrome DLP rules with Enforce cloud storage action and corp Google Drive, corp OneDrive for your organization as download destination. When this rule is triggered on a user's download, the file is not saved on the user's local storage and instead it is uploaded to the user's corp drive.

A TC39 proposal to add module import … with { type: "text" } statements to JavaScript. The import attribute loads text data as a string value.

Adds support for decoding JPEG XL (image/jxl) images in Blink using jxl-rs, a memory-safe pure Rust decoder (https://github.com/libjxl/jxl-rs). JPEG XL is a modern image format standardized as ISO/IEC 18181 that offers progressive decoding for improved perceived loading performance, support for wide color gamut, HDR, and high bit depth, and support for animation.

The :playing, :paused, :seeking, :buffering, :stalled, :muted, and :volume-locked CSS pseudo-classes match <audio> and <video> elements based on their state.

This is one of the focus areas in https://wpt.fyi/interop-2026.

Adds a "media-playback-while-not-visible" permission policy to allow embedders to pause audible media playback of embedded iframes which are currently hidden - i.e. "display" property set to "none"; "visibility" property set to "hidden"; or zero-area (width or height equal to 0). While hidden, attempts made by the embedded iframe to render audible media will be blocked. When the frame is shown again the prohibitions should be lifted. This should allow developers to build more user-friendly experiences and to also improve the performance by letting the browser handle the playback of content that is not visible to users.

Expose multiple HTML setting methods that provide a coherent story for dynamically inserting markup into an existing document.

• Positional methods (before/after/append/prepend/replaceWith) that take HTML as argument, effectively replacing insertAdjacentHTML.
• Streaming methods (stream{Append}HTML{Unsafe}) which return a WritableStream
• Passing {runScripts} as part of SetHTMLUnsafeOptions, mimicking createContextualFragment behavior.
• Supporting createParserOptions in trusted types, allowing trusted types to override scripting mode and sanitizer.

Adds support for passing custom HTTP request headers via WebTransportOptions and inspecting server response headers through the WebTransport instance. This allows web applications to supply metadata, authentication tokens, and custom parameters during the initial CONNECT handshake and access server-provided headers once the connection is established.

Fenced frames are nested frames that embed content onto a page without the ability to share data between the fenced frame and its embedder.

window.fence APIs include Fenced frames Ads reporting (FFAR) JS APIs that were created for privacy-safe ads reporting from FFs created using Protected Audience and SelectURL and getNestedConfigs() to support PA component ads.

This intent is for removing both of these. Fenced frames element removal will be two step as detailed below.

With the removal (or stub API replacement) of PA and selectURL, FFs can no longer be navigated and thus it is safe to remove them. Fenced frames are only able to be navigated using the urn:uuid in a FencedFrameConfig[1], which can only be created using the return values from runAdAuction and selectURL. These APIs are being deprecated and removed in M152 as per the following Intent threads: Protected Audience[2], Shared Storage[3].

Plan: Given that the fenced frames element can no longer be navigated, we propose removing the element from the code in the following phases:

1. M155: Keep the fenced frame element and its associated IDL dependencies as stubs. This is to ensure no JS call throws, e.g.calling fenced-frame-element.config.setSharedStorageContext().

2. M155: In the same milestone we will also remove the window.fence APIs completely. Since there is no FF document navigation, these APIs cannot be invoked anymore, so it will be a no-op.

3. M156 Canary/Beta: Begin a controlled rollout of the stub FF HTML element removal via a field trial. Note that removing the element will resolve it to HTMLUnknownElement.

At this point we are requesting approvals for all of the above steps.

4. M156 Stable: Assuming there are no regressions or breakage after reaching 1% stable, we will request additional approval for full removal of the FF element.

[1]https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/core/html/fenced_frame/fenced_frame_config.idl [2]https://groups.google.com/a/chromium.org/g/blink-dev/c/k_nubsMb97g/m/awPD4IGLBAAJ [3]https://groups.google.com/a/chromium.org/g/blink-dev/c/uh5Ke6qyegc/m/WFTFnhyJBAAJ