Re: WCAG 2.2 Focus Appearance, Normative Text

Hi Wilco,
> "Perceived control" isn't enough to go off in deciding the size of a component. This needs more clarification in the normative document.
As I said to Gregg: This is something we went over when discussing using the visual appearance as the basis for size.
https://www.w3.org/2022/03/08-ag-minutes#item05
https://www.w3.org/2022/03/22-ag-minutes#t08
We looked at defining decorative effects (no one managed to create a definition that didn’t leave you with more questions than answers), and using the content of the control (doesn’t really work for empty controls like text inputs & radio buttons).
The simplest answer seemed to be just to include the decorative effects. With the 4 x shortest side metric, there is buffer so that reasonable indicators would pass, or just make it 2px thick to be sure you’re passing.
Requiring that to be in the normative text creates a higher bar than we have for previous criteria, e.g. info & relationships, use of color, (text) contrast. All of those need someone to read the understanding and/or techniques to evaluate effectively.

> The current success criteria do not require counting how many pixels meet the contrast ratio. The new rule requires this, and has done it in a way that as far as I can tell cannot be done automatically. We have to be able to do better.
In practice I think that is similar to text-contrast on image / variable backgrounds. I’m sure you have similar advice where you’d say:
You’ve got white text on a variable background (various images), so you need a method to make sure the dark-fade behind the text is sufficient. Therefore, test it with a plain white image, and you can be sure it will always have contrast.
For focus-appearance, you’d keep an eye on areas where it might not contrast. If you have variable backgrounds, then recommend a thicker / dual-colour indicator.
Like with text-contrast, you only need to find one instance to make the recommendation that solves all instances. Find the worst one, test that.

> There is no color a browser could use to ensure sufficient contrast for text.
High contrast mode does this, as does selecting text (usually). The UA can change the background to text as well as the text-color.
Having said all that, I think we are re-treading the previous discussions.
Kind regards,
-Alastair