The <input type="week"> HTML element shows a week picker.

The @view-transition CSS rule sets whether a document opts-in to transitions between documents in a multi-page application. Both the old and new document must opt-in for a transition to be triggered.

The blocking="render" attribute for <link>, <script>, and <style> elements blocks rendering until the external script or stylesheet has been loaded. For <link rel="expect">, rendering is blocked until a specific element is in the DOM.

The ruby-overhang CSS property sets whether ruby annotations may overlap adjacent text.

An XRHand object, from the hand attribute of an XRInputSource object, represents a WebXR session's fully-articulated hand tracking model.

Compression Dictionary Transport is a mechanism for using designated HTTP responses as an external dictionary for future HTTP responses for compression schemes that support using external dictionaries (e.g., Brotli and Zstandard)

The box-decoration-break CSS property sets whether box decorations, such as borders or backgrounds, of an element divided across a page, column, or region wraps each fragment or splits across the break.

The justify-self CSS property aligns an item along a container's inline axis in block layouts, like it does in grid layouts. Likewise, the justify-items property sets a default justify-self value for all items in a container in a block layout.

The scrollsnapchanging and scrollsnapchange events fire when a scroll gesture changes the selected scroll snap target.

The CreateVirtualPressureSource WebDriver command creates artificial sources of compute pressure for testing without the need real device sources of compute pressure.

The calc-size() CSS function computes mathematical expressions that include height and width keyword values, for example calc-size(fit-content, size / 2). Not to be confused with the calc() CSS function, which cannot use keyword values.

The interpolate-size CSS property sets whether animations and transitions interpolate between a numeric value and a keyword value, such as from a fixed length to auto or fit-content.

The MediaStreamTrackProcessor and MediaStreamTrackGenerator APIs modify the contents of a media track for merging streams, applying real-time effects like funny hats, and content overlays.

You can animate elements between display: none and any other display value or animate between content-visibility: hidden and any other content-visibility value. This also applies to transitions.

The writingsuggestions HTML attribute turns on or off a browser's writing suggestions. Writing suggestions vary by browser. For example, if turned on then a browser might show inline text completions accepted by pressing Tab.

The <fencedframe> element embeds another HTML page into the current page in a more secure and privacy-preserving way than <iframe> elements.

The navigator.share() method invokes the device's native sharing mechanism and passes text, links, files, and other content to share targets. Also known as the Web Share API.

WebDriver BiDi is a bidirectional protocol that allows a WebDriver client and a browser to communicate with each other.

The notRestoredReasons property of a PerformanceNavigationTiming object explains why the current document was blocked from using the back/forward cache (also known as the bfcache) on navigation.

The PressureObserver API monitors CPU load, allowing you to adjust workloads in response to available computing resources. Also known as the Compute Pressure API.

Non-cookie storage access extends the requestStorageAccess() API to let content in cross-site iframes request access to first-party data beyond cookies.

The rel="expect" attribute for the <link> HTML element is a hint to the browser to block rendering until the element that the href value references is connected to the document and fully parsed.

The image/svg+xml data type (also known as the MIME type) for ClipboardItem objects represents SVG data written to or read from the clipboard.

The context-fill and context-stroke CSS values are used with fill and stroke in SVG <marker> or <use> elements to match a color from where they appear.

A single module in WebAssembly can have multiple memories.

The contextlost event for <canvas> fires when the canvas backing storage is lost, while the contextrestored event fires when it is recreated.

A long-animation-frame performance entry measures rendering updates that take longer than 50 milliseconds. Also known as LoAFs.

The text-spacing-trim CSS property controls spacing around CJK characters, avoiding excessive whitespace when using full-width punctuation characters.

The ::spelling-error and ::grammar-error CSS pseudo-elements match text that is highlighted as misspelled and grammatically incorrect, respectively.

The switch attribute, when present on an <input type="checkbox"> HTML element, renders a switch control with an on and off state instead of a checkbox control.