1022531 - Add CSS media query for High Contrast mode

Status: RESOLVED DUPLICATE of bug 425598

(Core :: CSS Parsing and Computation, defect)

Description

[Blair McBride [:Unfocused] (UNAVAILABLE)]

IE has implemented the media query -ms-high-contrast to allowing selecting based on the usage of a black-on-white or white-on-black high contrast mode:

http://msdn.microsoft.com/en-us/library/windows/apps/hh465764%28v=vs.85%29.aspx

It's currently a feature request for Media Queries Level 4:
http://wiki.csswg.org/spec/mediaqueries4#high-contrast-mode

In addition to this being an important accessibility feature for the web, we also want to use it (sooner rather than later) to help improve Firefox's UI.

Comment 1

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I recall a recent bug (though I can't find it) with discussion about adding a media query that we decided not to add because we didn't want to expose that information.  I'm wondering whether that's also an issue here, although I suspect it's not because I suspect that high contrast mode is also detectable through computed style given that we make it flip the color overriding prefs.