The text contrast rules should not exclude text in active user interface components

[dd8]

Both contrast rules exclude text in active and inactive widgets:

This rule applies to any visible character in a text node that is a child in the flat tree of an HTML element, except if the text node has an ancestor in the flat tree for which at least one of the following is true::
widget: the ancestor is a inheriting semantic widget; or

https://act-rules.github.io/rules/afw4f7
https://act-rules.github.io/rules/09o5cg

but the corresponding SCs only exclude text in inactive widgets:

Incidental: Text or images of text that are part of an inactive user interface component

https://www.w3.org/WAI/WCAG21/Understanding/contrast-minimum.html
https://www.w3.org/WAI/WCAG21/Understanding/contrast-enhanced.html

SC 1.4.11 understanding non-text contrast is clear that the text contrast SCs should apply to text inside widgets:

If a button with text also has a colored border, since the border does not provide the only indication there is no contrast requirement beyond the text contrast (1.4.3 Contrast (Minimum)).

Default link text is in the scope of 1.4.3 Contrast (Minimum), and the underline is sufficient to indicate the link.

https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast

[Jym77]

The extra difficulty with widgets is that we should test contrast in various "states" (visited links, focused widget, …) The rule initially excluded them because we didn't want to handle that extra difficulty at the time.
It should indeed handle them or having a rule dedicated for widgets. We've had some discussion about the idea last year.
See #1511 for longer discussion on the topic and links to even more discussions…

(note that this is "only" creating false negative (errors we don't spot), which is OK-ish; obviously not good for coverage, but not breaking the format either…)

[Jym77]

See also the discussion at #1763 and yesterday's CG call where we agreed we can drop the "no widget" restriction and we'll see later if/how we do something about states…