Experimental Chromium Web Platform Features

The ClipboardItem, which is the input to the async clipboard write method, now accepts string values in addition to Blobs in its constructor. ClipboardItemData can be a Blob, a string, or a Promise that resolves to either a Blob or a string.

Allows to style pseudo elements that are nested inside other pseudo elements. So far, support is defined for: ::before::marker ::after::marker With ::column::scroll-marker being supported in the future.

Document-Isolation-Policy allows a document to enable crossOriginIsolation for itself, without having to deploy COOP or COEP, and regardless of the crossOriginIsolation status of the page. The policy is backed by process isolation. Additionally, the document non-CORS cross-origin subresources will either be loaded without credentials or will need to have a CORP header.

One of the nice features of the Popover API is its light dismiss behavior. This chromestatus is about bringing that same capability to `<dialog>`. A new `closedby` attribute controls behavior: `<dialog closedby=none>` - no user-triggered closing of dialogs at all. `<dialog closedby=closerequest>` - user pressing ESC (or other close trigger) closes the dialog `<dialog closedby=any>` - user clicking outside the dialog, or pressing ESC, closes the dialog. Akin to `popover=auto` behavior.

getAllRecords() combines getAllKeys() with getAll() to enumerate both primary keys and values at the same time. For an IDBIndex, getAllRecords() also provides the record's index key in addition to the primary key and value. Lastly, getAllRecords() offers a new direction option to enumerate records sorted by key in descending order. This proposal adds getAllRecords() to both IDBObjectStore and IDBIndex. getAllRecords() creates a new IDBRequest that queries its IDBObjectStore or IDBIndex owner. The IDBRequest completes with an array of IDBRecord results. Each IDBRecord contains the key, primaryKey and value attributes. For IDBIndex, key is the record's index key. For IDBObjectStore, both key and primaryKey return the same value. The pre-existing IDBCursorWithValue interface contains the same attributes and values for both IDBObjectStore and IDBIndex. However, unlike getAllRecords(), a cursor may only read one record at a time.

A keyword for CSS sizing properties (e.g. 'width', 'height') that allows elements to grow to exactly fill their containing block's available space. It is similar to '100%', except the resulting size is applied to the element's margin box instead of the box indicated by 'box-sizing'. Using this keyword allows the element to keep its margins while still being as large as possible. An unprefixed version of '-webkit-fill-available'.

Import maps currently have to load before any ES module and there can only be a single import map per document. That makes them fragile and potentially slow to use in real-life scenarios: Any module that loads before them breaks the entire app, and in apps with many modules the become a large blocking resource, as the entire map for all possible modules needs to load first. This feature is to enable multiple import maps per document, by merging them in a consistent and deterministic way.

Resource timing: - responseStart returns the first response, either early hints (interim) or final - Expose the final response headers (2xx/4xx/5xx) time as finalResponseHeadersStart.

A shadow host with delegatesFocus set to true will delegate its focus to its first focusable child. On a mouse click event, the child will receive focus and the event will be marked as handled. No further event dispatching is done. This is a problem because the steps to handle text selection afterward are not ran and the selection does not recognize the focused element as part of the selection. We fix this by continuing event handling even after an element was delegate focused and update how selection recognizes having focus in a shadow tree.

Adds an "overallProgress" property to the JavaScript class Animation[1]. This property provides authors with a convenient and consistent representation of how far along an animation has advanced across its iterations and regardless of the nature of its timeline[2]. [1] https://developer.mozilla.org/en-US/docs/Web/API/Animation [2] https://developer.mozilla.org/en-US/docs/Web/API/AnimationTimeline

Allow anchor-size() values for inset and margin properties. Originally, anchor-size() was only allowed in sizing properties. The specification was changed to allow anchor-size() in insets and margins as well.

This change makes the HTML parser allow additional tags in <select> besides <option>, <optgroup>, and <hr>. This change is in support of the customizable <select> feature but is being shipped first because it can be done separately and has some compat risk which I'd like to get feedback on. This feature is gated by the temporary policy (SelectParserRelaxationEnabled). This is a temporary transition period, and the policy will stop working on milestone M136 Customizable select explainer: https://open-ui.org/components/customizableselect/ I did a compat analysis and determined that the vast majority of sites which would see the effects of the parser changes would not have their behavior changed. More details here: https://github.com/whatwg/html/issues/10310 If there are major issues with this change, I will reassess and make adjustments to the parser as needed.

It is useful for web authors do determine when their <dialog> elements open and close. popover already has `ToggleEvent` which is dispatched when a popover opens or closes, but <dialog> does not. The current way to detect when a <dialog> opens is to register a mutation observer to check for open, however, this is quite a lot of work where an event would be easier. This change incorporates the same `ToggleEvent`s that popovers dispatch, but for `<dialog>` elements: when `showModal` or `show` is called, <dialog> dispatches a ToggleEvent with newState=open. When a dialog is closed (via form or button or closewatcher) it should dispatch a ToggleEvent with newState=closed.

Add a bytes() method to the Request and Response interfaces, which returns a promise that resolves with a Uint8Array. While Request and Response have an arrayBuffer() method, we can't read directly from a buffer. We have to create a view such as a Uint8Array to read it. The bytes() method improves the ergonomics of getting the body of Request and Response.

Reference Target is a feature to enable using IDREF attributes such as `for` and `aria-labelledby` to refer to elements inside a component's shadow DOM, while maintaining encapsulation of the internal details of the shadow DOM. The main goal of this feature is to enable ARIA to work across shadow root boundaries. A component can specify an element in its shadow tree to act as its "reference target". When the host component is the target of a IDREF like a label's `for` attribute, the reference target becomes the effective target of the label. The shadow root specifies the ID of the target element inside the shadow DOM. This is done either in JavaScript with the `referenceTarget` attribute on the `ShadowRoot` object, or in HTML markup using the `shadowrootreferencetarget` attribute on the `<template>` element.

Support for "<string>" syntax component name for registered custom properties.

Allow relative colors in CSS (using the 'from' keyword) to use 'currentcolor' as a base. This will make it easy for web developers to set complementary colors, based on an element's text color, for that element's borders, shadows, backgrounds, etc. This feature also includes use cases where color functions are nested with a dependency on currentcolor, for example `color-mix(in srgb, rgb(from currentcolor r g b), white))` or `rgb(from rgb(from currentcolor 1 g b) b g r)`.

Font-variant-emoji CSS property provides users an easy way to control between colored (emoji-style) and monochromatic (text-style) emoji glyphs presentations. This can be also done by adding an emoji Variation Selector, specifically U+FE0E for text and U+FE0F for emojis, after each emoji codepoint. Using font-variant-emoji CSS property allows web developers to select between emoji style (colored) emoji presentation, text style (monochromatic) emoji presentation and unicode default emoji presentation [0]. This property only affects emojis that are part of a Unicode emoji presentation sequence [1]. [0] https://www.unicode.org/reports/tr51/tr51-25.html#Emoji_Presentation [1] http://www.unicode.org/emoji/charts/emoji-variants.html

This chromestatus represents the following related set of changes, which were resolved in https://github.com/whatwg/html/pull/9144#issuecomment-2195095228 and landed in https://github.com/whatwg/html/pull/10728: 1. add an imperative way to set invoker relationships between popovers: popover.showPopover({source}) 2. invoker relationships create implicit anchor element references.

Selection isCollapsed should return true if and only if the anchor and focus are the same. This should be true whether the selection starts/ends inside a light or a shadow tree. Currently, the Chrome implementation returns true if selection's anchor node is in a shadow tree, even if the selection itself is not collapsed. We fix this by removing the erroneous shadow tree check.

getClientCapabilities() method allows to determine which WebAuthn features are supported by the user's client. The method returns a list of supported capabilities, allowing developers to tailor authentication experiences and workflows based on the client's specific functionality.

Allow the creation of interactive scroll buttons as pseudo-elements, e.g. .scroller { overflow: auto; } .scroller::scroll-button(inline-start) { content: "<"; } .scroller::scroll-button(inline-end) { content: ">"; } These should be focusable, behaving as a button (including their UA styles). When activated, a scroll should be performed in the direction by some amount. When it is not possible to scroll in that direction, they should be disabled (and styled via :disabled), otherwise they are enabled (and styled via :enabled). Selector allows to define buttons in four logical directions: block-start, block-end, inline-start, inline-end; as well as four physical directions: up, down, left, right.

A JavaScript API for detecting the language of text, with confidence levels.

With this change <meter> elements with `appearance: none` will have a reasonable fallback style that matches Safari and Firefox instead of just disappearing from the page. As well developers will be able to custom style the <meter> elements. A feature flag MeterAppearanceNoneFallbackStyle is available until Chrome 133 to control this feature.

Many applications have multiple media flows of the same data type and often some of the flows are more important than others. The priority setting can be used to indicate the relative priority of various flows. The priority API allows the JavaScript applications to tell the browser whether a particular media flow is high, medium, low or of very low importance to the application.

This API allows processing of encoded media flowing through an RTCPeerConnection. Chromium shipped an early version of this API in 2020. Since then, the spec has changed and other browsers have shipped the updated version of the spec (Safari in 2022 and Firefox in 2023). This launch refers to the latest spec version.

Support of `sideways-rl` and `sideways-lr` keywords for `writing-mode` CSS property is added. They are vertical writing modes, and all letters are sideways.

The RTCDataChannel interface is part of the WebRTC standard, and represents a network channel which can be used for bidirectional peer-to-peer transfers of arbitrary data. This feature tracks exposing RTCDataChannel in dedicated workers, and allowing the transfer of RTCDataChannels to them workers. This will help reduce main thread contention and lead to smoother and more reliable WebRTC applications.