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Re: Does 1.4.10 essentially replace 1.4.4?


From: Patrick H. Lauke
Date: Sep 5, 2021 11:30AM

On 05/09/2021 18:22, glen walker wrote:
> Thanks Birkir and Patrick. I understand the fundamentals of both success
> criteria. My question was more academic in nature. If you want to conform
> to WCAG 2.1 AA then you must pass 1.4.10. If you pass 1.4.10, doesn't that
> (mostly) imply you also pass 1.4.4 so there's no need to test for 1.4.4?

They're independent, but yes if you start off testing 1.4.10 and it's
fine, it's likely that 1.4.4 passes as well (barring oddity of
intermediate viewport sizes if the developers have only set specific
ones and zooming to 200% would fall between the gaps and leave you in
unforeseen broken dimensions.

> That's another aspect that isn't completely clear (to me). 1.4.10 doesn't
> really say that *both* the width and height must be set. It just says that
> vertical scrolling content (such as English, German, Spanish, etc) doesn't
> require scrolling in two dimensions when at (exactly) 320 CSS px width. It
> doesn't say I must set the height too.
> Same with horizontal scrolling content (such as Mandarin, Korean, Arabic).
> The requirement refers to setting the height to 256 CSS px but doesn't say
> I must set the width too.
> Conceptually, if you think of the vertical scrolling case, if you don't
> have a horizontal scrollbar then you're good for 1.4.10 and since you're
> scrolling vertically, it doesn't really matter what the height of the
> browser is.

As the idea behind 1.4.10 was a desktop user on a 1280x768 display
zooming to 400%, it makes sense to test at that exact dimension. And
regardless of language, there might be situations (e.g. with fixed
headers/footer/etc) where there's no bi-directional scrollbars, but
where content is completely covered by other fixed/absolutely positioned
content. Or situations like a modal dialog that is centered and gets cut
off at the top and bottom, with no way for the user to scroll that modal
properly into view. Those are more general "without loss of information
or functionality" failures. (But yes this aspect is still quite vague in
1.4.10 and the understanding doc, and I'm sure some will argue that
those aren't failures of 1.4.10 at all)

Patrick H. Lauke

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