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Re: Does 1.4.10 essentially replace 1.4.4?


From: Patrick H. Lauke
Date: Sep 14, 2021 2:21AM

On 14/09/2021 09:09, Mitchell Evan wrote:
> I agree we should test 1.4.10 in a common desktop display size at 400% (or
> in a dev tools emulator equivalent). The most common aspect ratio of
> desktop screens
> <https://gs.statcounter.com/screen-resolution-stats/desktop/worldwide> is
> 1.78:1 with total usage over 60%, in screens such as 1280x720. Allowing for
> browser and OS toolbars as shown in the Understanding 1.4.10 example video
> <https://www.w3.org/WAI/WCAG21/Understanding/reflow.html#example-1-responsive-design>,
> the
> aspect ratio of the browser viewport (not the screen) is around 2:1.

However, 1.4.10 explicitly codifies one very specific value to test in
terms of width and height. That's the problem with that SC (and yes, it
also doesn't take into account the fact that viewports will indeed be
smaller owing to browser Chrome etc.

>>> 1.4.10 doesn't really say that *both* the width and height must be set.
> True — it's a common misunderstanding
> <https://github.com/act-rules/act-rules.github.io/issues/1318> that 1.4.10
> Reflow specifies a 1280x1024 viewport — at most 3% usage, with a very
> different aspect ratio of 1.25:1. The aspect ratio often makes a
> pass-or-fail difference with real-world consequences, when sticky content
> such as a fixed-position footer ends up covering the entire viewport.

Again, the inflexible wording of 1.4.10 cares not for what real-world
sizes of desktops are actually out there, unfortunately. Normatively, it
hardcodes 320 for width and 256 for height, with the explanation/excuse
that this is what you get (though you don't, really) for 1280x1024 at 400%.

It's a borked SC that was rushed without sufficient
scrutiny/forethought...but that's where we are.

Patrick H. Lauke

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