CSS background-repeat round and space

Allows CSS background images to be repeated without clipping.

CSS color() function

The CSS `color()` function allows the browser to display colors in any color space, such as the P3 color space which can display colors outside of the default sRGB color space.

CSS Grid Layout (level 1)

Method of using a grid concept to lay out content, providing a mechanism for authors to divide available space for layout into columns and rows using a set of predictable sizing behaviors. Includes support for all `grid-*` properties and the `fr` unit.

CSS Text Box

CSS `text-box` (and its longhands `text-box-trim` & `text-box-edge`) provide the ability to trim extra space over/under text glyphs at the start/end of a block to match specific font-provided metrics. This allows for more precise alignment and positioning of text.

ui-serif, ui-sans-serif, ui-monospace and ui-rounded values for font-family

Allows more control when choosing system interface fonts

CSS Flexible Box Layout Module

Method of positioning elements in horizontal or vertical stacks. Support includes all properties prefixed with `flex`, as well as `display: flex`, `display: inline-flex`, `align-content`, `align-items`, `align-self`, `justify-content` and `order`.

element api: getelementsbytagnamens: `getelementsbytagnamens(namespaceuri, "*")`

css property: text-decoration-skip-spaces: all

css property: text-spacing-trim: space-all

ecmascript 2020 (es11)