2021
30 featuresCSS logical properties control borders, size, margin, and padding with directions and dimensions relative to the writing mode. For example, in a left to right, top to bottom writing mode, block-end refers to the bottom. Also known as flow relative.
The Referrer-Policy HTTP header and referrerpolicy HTML attributes control whether requests have the Referer header and what information the header contains.
The WEBGL_color_buffer_float extension for WebGL 1.0 contexts adds the 32-bit floating-point type RGBA32F as a color-renderable format.
The WebGL2RenderingContext API is the "webgl2" rendering context for the <canvas> element. It represents a space for drawing two- and three-dimensional graphics and animations. It corresponds to OpenGL ES 3.0.
The aspect-ratio CSS property controls the width-to-height ratio of elements. For <img> and <video> elements, the width and height attributes used together with height: auto control the aspect ratio while the image/video is loading.
The font-family: system-ui CSS declaration uses the operating system default font for text.
The web authentication API allows you to create public key-based credentials and use them for authentication, such as when signing in. Also known as WebAuthn.
The EXT_shader_texture_lod extension for WebGL 1.0 and 2.0 contexts adds texture functions to the OpenGL ES Shading Language such that the shader writer explicitly controls the level of detail (LOD).
The visualViewport API provides a way to query and modify the user-visible viewport of a web page.
The tab-size CSS property sets the width of the tab character.
The ::file-selector-button CSS pseudo-element selects the button of a <input type="file"> element.
The AudioWorklet API runs module code in a separate thread, specifically for non-blocking, low latency audio processing.
Integer values pass bidirectionally between JavaScript and WebAssembly, converted to i64 values in WebAssembly or BigInt values in JavaScript.
The gap CSS property in a flexbox layout sets the size of the space between items.
The Intl.DisplayNames API provides localized names of language, region, script, and currency codes.
The Intl.ListFormat API creates a locale-aware formatter that turns iterable objects into localized strings.
The MediaRecorder API captures data generated by MediaStream or HTMLMediaElement objects for analysis, processing, or saving to disk. Also known as the Media Recording API.
The OES_fbo_render_mipmap extension for WebGL 1.0 contexts attaches any level of a texture to a framebuffer object.
The OfflineAudioContext API represents an audio processing graph that writes to an AudioBuffer instead of an output device.
A paint performance entry measures the duration of "paint" (also called "render") operations as a page loads. It measures the time to First Paint (FP) and First Contentful Paint (FCP), common metrics for perceived loading times.
Sign-extension operator instructions extend the width of 8-bit, 16-bit, and 32-bit values to 32-bit and 64-bit values.
The WeakRef and FinalizationRegistry objects hold references to garbage-collectable objects without creating strong references that prevent their garbage collection.
The rel="preload" attribute for the <link> HTML element requests resources, such as images or style sheets, that the page needs soon, so the browser may prioritize them for loading before rendering begins.
The :where() CSS functional pseudo-class takes a selector list as its argument, and matches any element that can be selected by one of the selectors in that list. It is functionally equivalent to the selectors in the list, but doesn't affect the CSS rule specificity.
The clip-path CSS property and SVG attribute set the visible area of an element. Everything outside the area will be hidden.