Use System colors for links - #12761
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[`/css/css-color/system-color-consistency.html`](https://wpt.fyi/results/css/css-color/system-color-consistency.html?label=experimental&label=master&aligned) ensures that system colors and the resolved `color` properties have the same value. When updating Servo to support dark mode, using the specified value for links isn't necessarily compatible in dark or light mode. In other parts of the specification, the system colors are used to denote the values, leaving it up to user agents to determine what the value should be. In fact, Edge currently fails this test and chooses a different value for LinkText in light mode. In dark mode, Edge passes the test. Therefore, to align with user agent choice and ensure that system colors are consistent with resolved colors, use LinkText for links.
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Aug 6, 2026
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This both updates Stylo to respect the dark/light mode color scheme flags, as well as enable the `color-scheme` CSS property. In doing so, it uncovered inconsistencies in the user agent styling, which required updating to use the system colors. If we want to change the color values, we need to update Stylo instead which specifies the chosen color values. This also uncovered an issue with the HTML spec where link elements don't necessarily use the LinkText system color [1]. Testing: newly passing WPT tests Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com> [1]: whatwg/html#12761
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This both updates Stylo to respect the dark/light mode color scheme flags, as well as enable the `color-scheme` CSS property. In doing so, it uncovered inconsistencies in the user agent styling, which required updating to use the system colors. If we want to change the color values, we need to update Stylo instead which specifies the chosen color values. This also uncovered an issue with the HTML spec where link elements don't necessarily use the LinkText system color [1]. Testing: newly passing WPT tests Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com> [1]: whatwg/html#12761
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Aug 7, 2026
This both updates Stylo to respect the dark/light mode color scheme flags, as well as enable the `color-scheme` CSS property. In doing so, it uncovered inconsistencies in the user agent styling, which required updating to use the system colors. If we want to change the color values, we need to update Stylo instead which specifies the chosen color values. This also uncovered an issue with the HTML spec where link elements don't necessarily use the LinkText system color [1]. Testing: newly passing WPT tests Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com> [1]: whatwg/html#12761
TimvdLippe
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Aug 7, 2026
This both updates Stylo to respect the dark/light mode color scheme flags, as well as enable the `color-scheme` CSS property. In doing so, it uncovered inconsistencies in the user agent styling, which required updating to use the system colors. If we want to change the color values, we need to update Stylo instead which specifies the chosen color values. This also uncovered an issue with the HTML spec where link elements don't necessarily use the LinkText system color [1]. Testing: newly passing WPT tests Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com> [1]: whatwg/html#12761
TimvdLippe
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Aug 7, 2026
This both updates Stylo to respect the dark/light mode color scheme flags, as well as enable the `color-scheme` CSS property. In doing so, it uncovered inconsistencies in the user agent styling, which required updating to use the system colors. If we want to change the color values, we need to update Stylo instead which specifies the chosen color values. This also uncovered an issue with the HTML spec where link elements don't necessarily use the LinkText system color [1]. Testing: newly passing WPT tests Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com> [1]: whatwg/html#12761
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) This both updates Stylo to respect the dark/light mode color scheme flags, as well as enable the `color-scheme` CSS property. In doing so, it uncovered inconsistencies in the user agent styling, which required updating to use the system colors. If we want to change the color values, we need to update Stylo instead which specifies the chosen color values. This also uncovered an issue with the HTML spec where link elements don't necessarily use the LinkText system color [1]. Stylo PR: servo/stylo#438 Testing: newly passing WPT tests Signed-off-by: Tim van der Lippe <tvanderlippe@gmail.com> [1]: whatwg/html#12761
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/css/css-color/system-color-consistency.htmlensuresthat system colors and the resolved
colorproperties have the same value. When updating Servo to support dark mode, using the specified value for links isn't necessarily compatible in dark or light mode.In other parts of the specification, the system colors are used to denote
the values, leaving it up to user agents to determine what the value should be. In fact, Edge currently fails this test and chooses a different value for LinkText in light mode. In dark mode, Edge passes the test.
Therefore, to align with user agent choice and ensure that system
colors are consistent with resolved colors, use system colors for links.
(See WHATWG Working Mode: Changes for more details.)
/rendering.html ( diff )