https://www.w3.org/TR/SVG2/painting.html#ColorRendering It has no normative requirements. Only Chrome implements passes all the [WPT tests for it](https://wpt.fyi/results/svg/painting/parsing/color-rendering-valid.svg?label=master&product=chrome%5Bexperimental%5D&product=edge&product=firefox%5Bexperimental%5D&product=safari%5Bexperimental%5D&aligned) of it and I don't know what they do with it beyond parsing it.