> Then maybe we want to refer to HTML/CSS/SVG?

Sounds good.

> Our convention is to say
>
>   see the Info node `(emacs) Colors for Faces'
>
> to refer to the Info manual.

Thanks! I was looking for that syntax :-)

> Also, I think this change warrants an entry in NEWS.

Okay.

This patch also incorporates Andy's suggestions, and adds some tests.