2.4.7 Focus Visible - explanation/understanding addition about "mode of operation"?

[patrickhlauke]

The current wording of the SC

2.4.7 Focus Visible: Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible

talks about a "mode of operation". However, the understanding document https://www.w3.org/TR/UNDERSTANDING-WCAG20/navigation-mechanisms-focus-visible.html currently doesn't mention/explain this at all. What exactly is meant by "a mode of operation"? A user setting? Does the act of using a keyboard itself constitute a "mode of operation"? It would be good to get at least a mention of this in understanding.

[alastc]

Going through old issues, but I've been updating focus-visible so this is relevant.

For HTML-based web content I've generally ignored this phrase, assuming the default 'mode of operation' is the only mode of operation. I was assuming it accounted for flash or something, where there might be multiple modes of operation?

In the new draft, how about a line such as:

Where the success criterion says “mode of operation”, this is to account for platforms which may not always show a focus indicator. In most cases there is only one mode of operation so this success criteria applies.

[patrickhlauke]

Context of this is question was also certain arguments for/against the use of :focus-visible, which allows you to style the focus state when the browser/UA/platform itself would show it. case in point buttons or links that when clicked with the mouse wouldn't show an outline/focus indicator by default, but when focused via keyboard they do. There have been various discussions saying this is bad/contravenes 2.4.7, whereas i'd argue that using :focus-visible is within the spirit of 2.4.7, as there IS a mode of operation where the keyboard focus indicator is visible...and that's when the user is actually using the keyboard to navigate. whether or not it shows the focus indicator when operating things purely with a mouse (or touchscreen, or whatever) is then not a failure, provided that once they switch to using keyboard it becomes visible

[patrickhlauke]

in short, if the WG agrees with my above interpretation/assessment, i'd rather have the understanding doc explain this idea of "mode of operation" as in "a way in which the user controls/operates their UA / which input method they use", and perhaps a positive technique that shows the use of :focus-visible to satisfy 2.4.7

[alastc]

Huh, I hadn't come across that argument before. To me the key words in the SC are "keyboard focus indicator", not focus indicator or mouse-focus indicator.

How about:

“Mode of operation”, accounts for platforms which may not always show a focus indicator, or only show the focus indicator when the keyboard is used. User agents may optimse when the focus indicator is shown, such as only showing it when a keyboard is used.

Or suggest something...

[patrickhlauke]

I hadn't come across that argument before

the most recent one I can remember was here https://twitter.com/patrick_h_lauke/status/1048303192147152896

I'll ponder this / put it in my to-do list :)

[alastc]

Well, that paragraph above is in the the focus-more-visible draft for WCAG 2.2. whether that replaces the current 2.4.7 or is as well-as depends on the discussion on the list at the moment.

[patrickhlauke]

yeah sorry, wasn't meaning that your suggested text was insufficient or anything. just not had time to fully review that whole hornets' nest. may end up with more like a positive technique that shows it's kosher to use :focus-visible but otherwise suppress focus indication as result of mouse interaction or similar, then it's crystal clear that we think that's in line with the spirit here (assuming we do)

[alastc]

Noting that the above text in the understanding doc for 2.4.7 now:
https://www.w3.org/WAI/WCAG21/Understanding/focus-visible.html

Can we close this one? A PR for a new technique would be separate anyway...

[patrickhlauke]

Yup, all good to close this. If I get a chance/remember, I'll do a tiny positive technique using :focus-visible.

[alastc]

Re-opening as it was missed by the group when included in the focus-visible enhanced PR.

[mbgower]

I'd want us to be careful with a sufficient technique using :focus-visible. We should consider a matching failure technique where the designated values (outline, background) by the author cause the focus visibility to fail.

BTW, Mozilla has a nice page showing some of the different pseudo-classes.

https://developer.mozilla.org/en-US/docs/Web/CSS/:focus-visible

[alastc]

In the call we settled on this text:

“Mode of operation” accounts for user-agents which may not always show a focus indicator, or only show the focus indicator when the keyboard is used. User-agents may optimize when the focus indicator is shown, such as only showing it when a keyboard is used. Authors are responsible for providing at least one mode of operation where the focus is visible.

I'll add it to the focus-visible branch.

[alastc]

Added in this update, so closing.