Does G183 only apply to "links and controls" with additional requirements or in general?

[JAWS-test]

If I understood @patrickhlauke correctly (#857), the WCAG SCs are normative and all other documents (Understanding, Failure etc.) are not normative. This means that the latter can explain the SCs, but cannot extend, restrict or even contradict them. SC 1.4.1 just says: "Color is not used as the only visual means..." - and there's not a single hint of a possible exception.
But then there is this https://www.w3.org/WAI/WCAG21/Techniques/general/G183 which restricts 1.4.1. How can that be?
Furthermore, 1.4.11 refers to this G183 and uses it for the examples in Figure 6 and 7. But:

• which contrast ratio is now sufficient according to 1.4.11, if 3:1 is sufficient for links?
• and why should a contrast difference be sufficient for the stars of Figure 6 and 7, when G183 clearly states: "it can be used if additional visual confirmation is available when a user points or tabs to the link". And how does the "additional visual confirmation" look like for the stars? The text also does not say that the stars are interactive elements. It could also be just an illustration of the rating - and then there would certainly be no additional effects as with the links.

I'm not against the contents of G183, but

• in WCAG 3.0, the desired exceptions should already be considered when writing the SCs
• and G183 should already now be revised to apply to other elements, if referred to in 1.4.11. Otherwise, the reference in 1.4.11 should be removed.

See also: #201

[alastc]

SC 1.4.1 just says: "Color is not used as the only visual means..." - and there's not a single hint of a possible exception.
But then there is G183 ... "Using a contrast ratio of 3:1 with surrounding text and providing additional visual cues on focus for links or controls where color alone is used to identify them"
How can that be?

Because contrast is not "color alone". I.e. a contrast difference is another "visual means of conveying information".

and why should a contrast difference be sufficient for the stars of Figure 6 and 7

It isn't a contrast difference, in figure 6, both examples use a change of (contrasting) shape to convey the information. Figure 7 does rely on a (non-contrasting) color difference, it's a failing example.

[JAWS-test]

I reopen the issue because I think the distinction between 1.4.1 and 1.4.11 / 1.4.3 should be clearer. If 1.4.1 is only about the hue and not about color (as a general term for hue, brightness, saturation), does 1.4.1 only apply if the contrast of two colors is identical? Because otherwise there is another visual means: The contrast. Unfortunately, there is no requirement for contrast unless the elements are directly adjacent. So this is all quite unclearly regulated. I suggest:

• 1.4.11 is about the contrast of adjacent content (foreground and background)
• 1.4.1 treats color as a general term (for hue, brightness, and saturation), but allows the exception that color coding is fine if the contrast is more than 3:1. This should be formulated directly in the Understanding. It should also be stated that the use of this exception is not recommended. I can write such an amendment if there are no objections to its content.

[alastc]

If you'd like to propose an update to the understanding doc, please fork the repo and send in a pull request referencing this issue.

I recommend keeping it very focused on this change, adding other ammendments will make it harder to approve.

[JAWS-test]

I would like to add the following note to Understanding 1.4.1. If all interested parties agree, I will create a PR. Since I do not speak English, please also make linguistic corrections. Thanks

"Note:
If the contrast ratio between two colors is greater than 3:1, this is considered as an other visual mean and this success criterion is met. However, it is recommended to use other visual means instead of or in addition to contrast differences to meet this sucess criterion."

A justification for the restriction ("However, it is recommended to use other visual means instead of or in addition to contrast differences to meet this sucess criterion") may need to be added to the text. The justification would be, for example "When using the High Contrast Mode or when adapting the CSS to user needs, color differences are sometimes no longer visible. If only color with sufficient contrasts is used, this criterion is fulfilled, but there may be a violation of success criterion 1.3.1.".