Non-sRGB interpolation methods were added for CSS gradients but the Cairo backend does not yet support them. This tracks adding support. Currently only a few tests are failing mostly due to the challenging nature of writing ref tests for gradients: fast/gradients/gradient-using-specified-hue-interpolation-method-hsl.html fast/gradients/gradient-using-specified-hue-interpolation-method-hwb.html fast/gradients/gradient-using-specified-hue-interpolation-method-lch.html fast/gradients/gradient-using-specified-hue-interpolation-method-oklch.html
<rdar://problem/100656025>