[gardaani]

> The problem is sources of color data that don't have a tag. CSS is a big offender. CSS doesn't specify the colorspace of colors, so typically browsers will just send whatever is in there directly to the display.

CSS defines that all hex and rgb() colors are always in the sRGB colorspace. There is also support for other colorspaces, such as P3 and Adobe RGB. [1]

The Safari web browser does color management for wide gamut displays correctly, so #ff0000 looks correct and not too vibrant. The biggest offenders are Chrome and Firefox, because they are not color managed. Those web browsers (and Windows) give you the wrong colors.

> There are also plenty of images out there that don't include color space tags, so it's undefined as to what colors they're actually trying to display. Some software assumes sRGB.

Images without colorspace tags have been defined to be sRGB images by the web specs [1] and all web browsers should already do that. Other software may do something else, as you said. I hope all software will copy how web does it.

[1] https://www.w3.org/TR/css-color-4/

[formerly_proven]

Firefox (and I think Chrome as well) does color management for images, and I think they even do it correctly these days (i.e. no tag = assume sRGB), which they did not for some time (out of the box).

FWIW I think the Windows approach to color management has proven wrong and off-base for today's world. It stems from the 90s where color management was seen as something only "pro" applications would ever need to do, so it was okay to require a lot of effort from those few application developers to implement color management in their apps. The MacOS approach where applications tag their surfaces with one of a few standard color spaces and the system does the rest is less powerful in theory but, on the other hand, means that things will actually work. Plus, I think MacOS has escape hatches so that apps can do their own color management based on output device ICC profiles if they really want to.