The WebGLQuery interface is part of the WebGL 2 API and provides ways to asynchronously query for information. By default, occlusion queries and primitive queries are available.
The HTML <multicol> element was an experimental element designed to allow multi-column layouts. It never got any significant traction and is not implemented in any major browsers.
The Object.entries() method returns an array of a given object's own enumerable property [key, value] pairs, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).
The Object.values() method returns an array of a given object's own enumerable property values, in the same order as that provided by a for...in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).
The static SIMD.%type%.not() method returns a new instance with the bitwise logical NOT of the lane values (~a). This operation exists only on integer and boolean SIMD types.
The padEnd() method pads the current string with a given string (eventually repeated) so that the resulting string reaches a given length. The pad is applied from the end (right) of the current string.
The padStart() method pads the current string with a given string (eventually repeated) so that the resulting string reaches a given length. The pad is applied from the start (left) of the current string.
Property names that are prefixed with --, like --example-name, represent custom properties that contain a value than can be reused throughout the document using the (var()) function.
The :any()pseudo-class lets you quickly construct sets of similar selectors by establishing groups from which any of the included items will match. This is an alternative to having to repeat the entire selector for the one item that varies.
The :dir CSS pseudo-class matches elements based on the directionality of the text contained in it. In HTML, the direction is determined by the dir attribute. For other document types there may be other document methods for determining the language.
The @keyframes CSS at-rule lets authors control the intermediate steps in a CSS animation sequence by establishing keyframes (or waypoints) along the animation sequence that must be reached by certain points during the animation. This gives you more specific control over the intermediate steps of the animation sequence than you'd get when letting the browser handle everything automatically.