Experimental Chromium Web Platform Features
Experimental web platform features are not yet part of the official web platform specifications and are marked as "experimental" in Chromium.
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Added in Chromium 130 currentPolypane 22
- CSS At Property String Syntax
CSSAtPropertyStringSyntax
chromestatus.comSupport for "<string>" syntax component name for registered custom properties.
- CSS Relative Color Supports Currentcolor
CSSRelativeColorSupportsCurrentcolor
chromestatus.comAllow 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
FontVariantEmoji
chromestatus.comFont-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
- Popover Anchor Relationships
PopoverAnchorRelationships
chromestatus.comThis 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 Is Collapsed Shadow DOM Support
SelectionIsCollapsedShadowDOMSupport
chromestatus.comSelection 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.
- Web Authentication Client Capabilities
WebAuthenticationClientCapabilities
chromestatus.comgetClientCapabilities() 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.
- New features in Chromium 130 with missing descriptionCanvas2d Layers With Options
Canvas2dLayersWithOptions
Canvas2d Text Metrics ShapingCanvas2dTextMetricsShaping
CSS Pseudo ColumnCSSPseudoColumn
CSS Relative Color Late Resolve AlwaysCSSRelativeColorLateResolveAlways
CSS Visibility InertCSSVisibilityInert
Document Policy Expect No Linked ResourcesDocumentPolicyExpectNoLinkedResources
Storage Access HeaderStorageAccessHeader
System Fallback Emoji V S SupportSystemFallbackEmojiVSSupport
Web App InstallationWebAppInstallation
Added in Chromium 129
- Language Detection API
LanguageDetectionAPI
chromestatus.comA JavaScript API for detecting the language of text, with confidence levels.
- Meter Appearance None Fallback Style
MeterAppearanceNoneFallbackStyle
chromestatus.comWith 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.
- RTC Data Channel Priority
RTCDataChannelPriority
chromestatus.comMany 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.
- RTC Rtp Script Transform
RTCRtpScriptTransform
chromestatus.comThis 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.
- Sideways Writing Modes
SidewaysWritingModes
chromestatus.comSupport of `sideways-rl` and `sideways-lr` keywords for `writing-mode` CSS property is added. They are vertical writing modes, and all letters are sideways.
- Transferable RTC Data Channel
TransferableRTCDataChannel
chromestatus.comThe 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.
- New features in Chromium 129 with missing descriptionCanvas Place Element
CanvasPlaceElement
CSS Pseudo Scroll ButtonsCSSPseudoScrollButtons
Event Timing Handle Keyboard Event Simulated ClickEventTimingHandleKeyboardEventSimulatedClick
Event Timing Tap Stop Scroll No Interaction IdEventTimingTapStopScrollNoInteractionId
Nested View TransitionNestedViewTransition
Partitioned PopinsPartitionedPopins
Pointer Event Targets In Event ListsPointerEventTargetsInEventLists
Pseudo Elements FocusablePseudoElementsFocusable
Shape Outside Writing Mode FixShapeOutsideWritingModeFix
Web Authentication Attestation FormatsWebAuthenticationAttestationFormats
Added in Chromium 128 Polypane 21.1
- Box Decoration Break
BoxDecorationBreak
chromestatus.comSupport box-decoration-break:clone both for inline fragmentation (line layout) and block fragmentation (pagination for printing, multicol). Traditionally in Blink, only box-decoration-break:slice (the initial value) has been supported for block fragmentation, whereas for inline fragmentation, box-decoration-break:clone was also supported, but only when using the prefixed -webkit-box-decoration-break property. See https://drafts.csswg.org/css-break/#break-decoration
- Coalesce Selectionchange Event
CoalesceSelectionchangeEvent
chromestatus.comThis feature is not to fire selectionchange event when there is already one pending. For web developers, selectionchange event listeners will be called less often with this feature. Before this feature, every time the mutation of the selection on one target(input/textarea/document) would make the listener to be called once. Now with this feature, before the selectionchange event listner is finally called, multiple mutations of the selection on one target would make the listener to be called only once.
- Controlled Frame
ControlledFrame
chromestatus.comAdds a Controlled Frame API available only to Isolated Web Apps (IWAs). This work will add a new Controlled Frame API which is only available to Isolated Web Apps (IWAs). Like similarly-named APIs on other platforms, Controlled Frame allows embedding all content, even third party content that can't be embedded in <iframe>. Controlled Frame also allows controlling embedded content with a collection of API methods and events. For more info on Isolated Web Apps, see the IWA explainer: https://github.com/WICG/isolated-web-apps/blob/main/README.md
- CSS Inset Area Value
CSSInsetAreaValue
chromestatus.comReplaces the inset-area() function with inset-area values directly within position-try-fallbacks. This means that you now just write e.g. position-try-fallbacks:top instead of position-try-fallbacks:inset-area(top).
- CSS Reading Flow
CSSReadingFlow
chromestatus.comThe reading-flow CSS property controls the order in which elements in a flex or grid layout are rendered to speech or are navigated to when using (linear) sequential navigation methods. This feature implements the listed values: * normal * flex-visual * flex-flow * grid-rows * grid-columns * grid-order
- Multi Smooth Scroll Into View
MultiSmoothScrollIntoView
chromestatus.comThis feature allows scrollIntoView with behavior: "smooth" to run concurrently on scroll containers which are neither descendants nor ancestors of one another. scrollIntoView with behavior: "smooth" is a JavaScript method developers can use to cause scroll containers to scroll to their descendants via a gentle scroll animation. This feature fixes Chrome's implementation of the API so that ongoing scrollIntoView animations are not cancelled by unrelated scrolls on other scroll containers. This codepen[1] demonstrates the difference in behavior between Chrome and other browsers. The features also fixes cases where Chrome fails to scroll to a page's fragment anchor because of a competing scrollIntoView that is invoked when the page loads. [1] https://codepen.io/awogbemila/pen/GRaJQMG
- Page Margin Boxes
PageMarginBoxes
chromestatus.comAdd support for page margin boxes, when printing a web document, or exporting it as PDF. @page margin boxes allows an author to define the contents in the margin area of a page, for instance to provide custom headers and footers, rather than using the built-in headers and footers generated by the browser. A margin box is defined via an at-rule inside a CSS @page rule. There are 16 rules defined, one for each page margin box. There's one margin box for each of the 4 corners on the page, and three (start, middle, end) for each of the 4 sides. The appearance and the contents of a margin box are specified with CSS properties inside the at-rule, including the "content" property. Counters are also to be supported, for page numbering. The specification defines two special counter names: "page" for the current page number, and "pages" for the total number of pages.
- Select Parser Relaxation
SelectParserRelaxation
chromestatus.comThis 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.
- WebGPU HDR
WebGPUHDR
chromestatus.comAdds tone mapping parameters to the WebGPU canvas configuration, and adds options of "standard" (the current behavior of restricting content to the SDR range of the display) as the default, and "extended" (not imposing this restriction) as a new behavior. This allows WebGPU content to use the full range of a display.
- Web Identity Digital Credentials
WebIdentityDigitalCredentials
chromestatus.comWebsites can and do get credentials from mobile wallet apps through a variety of mechanisms today (custom URL handlers, QR code scanning, etc.). This Web Platform feature would allow sites to request identity information from wallets via Android's IdentityCredential CredMan system. It is extensible to support multiple credential formats (eg. ISO mDoc and W3C verifiable credential) and allows multiple wallet apps to be used. Mechanisms are being added to help reduce the risk of ecosystem-scale abuse of real-world identity (see https://docs.google.com/document/u/1/d/1L68tmNXCQXucsCV8eS8CBd_F9FZ6TNwKNOaFkA8RfwI/edit).
- New features in Chromium 128 with missing descriptionCSS Line Clamp
CSSLineClamp
CSS Text Box TrimCSSTextBoxTrim
File System Observer UnobserveFileSystemObserverUnobserve
Report Event Timing At Visibility ChangeReportEventTimingAtVisibilityChange
Selection Across Shadow DOMSelectionAcrossShadowDOM
Web Codecs Video Encoder BuffersWebCodecsVideoEncoderBuffers
WebGPU Subgroups FeaturesWebGPUSubgroupsFeatures
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