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Re: [csswg-drafts] [mediaqueries-5] prefers-contrast: infer contrast preference from forced colors (#5224)

From: Zeke Medley via GitHub <sysbot+gh@w3.org>
Date: Mon, 27 Jul 2020 17:40:25 +0000
To: public-css-archive@w3.org
Message-ID: <issue_comment.created-664538894-1595871624-sysbot+gh@w3.org>
Thanks for taking a look at this and adding to the spec. I agree that having some interoperability would be good especially given that we already have some baseline from the WCAG. Ideally, `prefers-contrast` should behave the same across browsers.

To add some context, I went through the Windows high contrast themes that are installed by default and calculated their contrast between text and background colors.

### High Contrast 1 
- Contrast ratio: `19.56:1`.
### High Contrast 2
- Contrast ratio: `15.30:1`
### High Contrast 3/4
- Contrast ratio: `21:1`.

Those high contrasts would certainly suggest that a "high contrast" preference is one much higher than the WCAG values. If the inverse is true then perhaps a low contrast is also much lower? It would be nice to get some input from someone who knows why colors like that were chosen and then build a decision about contrast thresholds off of that.

GitHub Notification of comment by ZekeMedley
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/5224#issuecomment-664538894 using your GitHub account
Received on Monday, 27 July 2020 17:40:27 UTC

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