Around the last week of March 2023, I intend to turn the new [color-4] additions on by default on all platforms. It has been developed behind the “layout.css.more_color_4.enabled” preference.
Summary: New color functionality was added to the CSS color specification (level 4) that will be very useful to developers. They include new color types, lab(), lch(), oklab() and oklch(). Also some new color spaces were introduced through the color() function, namely srgb (equivalent to the existing rgb/rgba() functions), srgb-linear, display-p3, a98-rgb, prophoto-rgb, rec2020. Color can also be specified in the XYZ color format through the color() function. Some additional features like support for the “none” keyword is now also supported.
Bug to turn on by default: https://bugzilla.mozilla.org/show_bug.cgi?id=1813497
Platform coverage: All platforms where Gecko is supported.
DevTools bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1632548
Blink: Shipped in version 111 (Released 2023-03-07)
WebKit: Shipped in version 15 (Released 2021-09-20)
Web platform tests: https://wpt.fyi/results/css/css-color