Gregory's Server@hsivonen gamut mapping algorithms used for photos are totally different and focus on maintaining the relationships between the colors in the image, whereas in the CSS one we focus on preserving as much of the individual color “identity” as possible (hue and lightness). CSS gamut mapping does not affect embedded images.
@leaverou Doesn’t that break the ability to match CSS colors to image colors? Seems like an unhappy result if the page author intends a CSS-colored thing to seamlessly continue from an image and it looks like that on their screen but not on other screens.