On Mon, Jun 15, 2015 at 12:00 PM, Maciej Stachowiak <m...@apple.com> wrote: > For similar reasons, it seemed better to reuse the existing theme-color meta > (which gives license to darken or lighten the color as needed).
Agreed; along with Ted's observation that theme-color hits at least the 80/20 use-case, I don't think we need anything new for colors here. UAs SHOULD look at the lightness of the theme-color and make adjustments as appropriate. (Tho only if necessary - Twitter blue, for example, should stay unless it's really bad. Icons don't need to meet the same a11y contrast guidelines as text, I wouldn't think, giving you a lot of latitude to keep the specified color exactly in most circumstances.)