1955572 - Add "prefers-contrast: more" switch/emulation in Developer Tools.

Status: NEW

(DevTools :: Inspector, enhancement, P3)

Description

[Jan Honza Odvarko [:Honza] (always need-info? me)]

Originally requested here:
https://connect.mozilla.org/t5/ideas/add-quot-prefers-contrast-more-quot-switch-emulation-in/idi-p/90741

For testing it would be very helpful if you could force the use of the "prefers-contrast: more" media query via a switch in developer tools. Chrome provides settings for forcing several accessibility options (hidden under the optional "rendering" settings), I'd very much like Firefox to have this as well. Maybe it could even be a user setting, so users don't have to enable high contrast mode in their OS just to tell the browser to use "prefers-contrast: more" stylesheets.

Comment 1

[C. Martin]

Thanks for adding this as a feature request (I made the original suggestion)!

To have this as an user option seems even more desirable and logical to me, after I found out that Windows 11 always enforces a color scheme along with enabling high contrast mode, thus overriding everything you define in a media query "prefers-contrast: more" and making such a stylesheet useless for all Windows users. I don't get Microsoft's thinking on this, it surely won't encourage developers to spend time on such an important accessibility feature.

OS X and Linux handle color schemes and high contrast mode separately which makes a lot more sense to me.
But in the end I think it should be an user setting in every browser and not (solely) dependent on OS settings.

Comment 2

[Nicolas Chevobbe [:nchevobbe]]

Looks similar to Bug 1591539 , and probably would require Bug 1916591

I know the accessibility team is doing some work to add control for users to set colors at the browser level (see https://blog.monotonous.org/2025/03/06/New-Contrast-Control-Settings/), so there might be things we could rely on at some point