Hi Alastair, I think what you are saying about the thickness is that if the color is < 3:1 then we would allow size difference to count – is that correct? I guess we’d need to agree as a group as to when < 3:1 was acceptable and then determine what is a apparent enough change for users to detect.
Jonathan
From: Alastair Campbell <acampbell@nomensa.com>
Sent: Friday, August 9, 2019 10:33 AM
To: public-low-vision-a11y-tf <public-low-vision-a11y-tf@w3.org>
Subject: Re: focus visible
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Hi everyone,
I wasn’t sure from the minutes if there were any additions / thoughts about the new focus-visible criteria?
Jim’s comment (in a co-ordination call) about separation of lines helping perception helped triggered a thought.
This is my test page with some black/white/grey examples to test various options:
https://alastairc.uk/tests/wcag21-examples/ntc-focus-styles.html
Comparing examples 4 & 6 (dark border with dark outline vs an out-set outline), I wondered about adding another requirement such as:
Minimum focus thickness: If the focus indication area is adjacent to a color with which it does not have a 3:1 contrast ratio difference, the thickness of the focus indicator is at least 2 CSS pixel.
I.e. if you put a dark outline around a dark button, it must be 2px thick. If you separate it, it can be 1px thick.
So this would fail:
[cid:image004.png@01D5515E.C5B24CF0]
But either of these would pass:
[cid:image006.png@01D5515E.C5B24CF0]
[cid:image008.png@01D5515E.C5B24CF0]
It probably needs re-wording, but does that idea make sense? And if so, are there any pointers to supporting research?
Cheers,
-Alastair
