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Number of posts in this thread: 12 (In chronological order)

From: Kalle Lahtinen
Date: Thu, Nov 28 2019 4:55AM
Subject: 200% website scaling
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Hi

I'm doing accessibility testing for my company and seem to come to a
problem with Success Criterion 1.4.4 Resize text. It makes a big
difference if user has Windows scaling on operating system. If user has 100
% scaling on Windows most my test go thru with 200% zoom in the browser.
But if I have 175 % scaling in Windows then 200% zoom the website is not
usable

So is there some standard or something that says what is acceptable scaling
level and also what resolution and screen size are minimum to test.

Im sorry if did not make any sense but ask if you need more information on
the issue.

--
Kalle Lahtinen

Protacon Oy
= EMAIL ADDRESS REMOVED =

From: glen walker
Date: Thu, Nov 28 2019 11:55AM
Subject: Re: 200% website scaling
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In Windows 10, the "Make everything bigger" option (scaling) is in the
"Ease of Access" settings, which can be considered an accessibility
feature. 1.4.4 says "...text can be resized *without assistive technology *up
to 200 percent...".

So if your page looks good at 200% zoom in browser and windows scaling is
100% (essentially assistive technology is turned off), then I'd say you're
ok. If you change your scaling (turning assistive technology on), then
while it would be nice to support browser zoom, if it doesn't completely
work, it's not necessarily a 1.4.4 failure.

It might depend what you mean by "not usable". If your page does not
reflow properly, the problem might be reproducible without scaling turned
on, in which case it would be a 1.4.4 problem.


On Thu, Nov 28, 2019 at 4:55 AM Kalle Lahtinen < = EMAIL ADDRESS REMOVED = >
wrote:

> Hi
>
> I'm doing accessibility testing for my company and seem to come to a
> problem with Success Criterion 1.4.4 Resize text. It makes a big
> difference if user has Windows scaling on operating system. If user has 100
> % scaling on Windows most my test go thru with 200% zoom in the browser.
> But if I have 175 % scaling in Windows then 200% zoom the website is not
> usable
>
> So is there some standard or something that says what is acceptable scaling
> level and also what resolution and screen size are minimum to test.
>
> Im sorry if did not make any sense but ask if you need more information on
> the issue.
>
> --
> Kalle Lahtinen
>
> Protacon Oy
> = EMAIL ADDRESS REMOVED =
> > > > >

From: Patrick H. Lauke
Date: Thu, Nov 28 2019 12:45PM
Subject: Re: 200% website scaling
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On 28/11/2019 18:55, glen walker wrote:
> In Windows 10, the "Make everything bigger" option (scaling) is in the
> "Ease of Access" settings, which can be considered an accessibility
> feature. 1.4.4 says "...text can be resized *without assistive technology *up
> to 200 percent...".

Not really. It's a display setting, not an accessibility setting.

Changing the system's scaling will, in essence, change the number of
logical/CSS pixels used. It changes the relationship between the
hardware pixels on the display, and the logical/display pixels used.

So what is happening here is that when you have a higher scaling than
100%, you're essentially making the viewport in the browser smaller.
i.e. the same problems would appear if you ran your browser window not
full-screen/maximised, but at a smaller windowed size.

Resize text in theory applies to any possible viewport size. At any
possible viewport size, a user should be able to resize text up to 200%
without adverse effects (things being cut off, overlapping ... but note
that scrollbars are fine, they're not prohibited by 1.4.4).

Long story short: if you're having situations in which 200% zoom in
browser does lead to unusable content (in terms of content being cut off
and unreachable, even with scrolling, over overlapping), then yes that's
a failure of 1.4.4.

> So if your page looks good at 200% zoom in browser and windows scaling is
> 100% (essentially assistive technology is turned off), then I'd say you're
> ok. If you change your scaling (turning assistive technology on), then
> while it would be nice to support browser zoom, if it doesn't completely
> work, it's not necessarily a 1.4.4 failure.
>
> It might depend what you mean by "not usable". If your page does not
> reflow properly, the problem might be reproducible without scaling turned
> on, in which case it would be a 1.4.4 problem.

Let's not confuse the matter by talking about reflow, which has nothing
to do with 1.4.4. That's a 1.4.10 thing. And yes, there, content should
adapt/reflow to the viewport correctly and not cause two-directional
scrollbars.

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke
http://flickr.com/photos/redux/ | http://redux.deviantart.com
twitter: @patrick_h_lauke | skype: patrick_h_lauke

From: glen walker
Date: Fri, Nov 29 2019 10:40AM
Subject: Re: 200% website scaling
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One of the great (and aggravating) things about accessibility is that some
issues are subjective.

> Not really. It's a display setting, not an accessibility setting.

As mentioned in my reply. "Make everything bigger" (scaling) is the "Ease
of Access" settings. Those are accessibility settings.

> Let's not confuse the matter by talking about reflow, which has nothing
to do with 1.4.4

Sure it does. You even said so yourself when you said "At any possible
viewport size, a user should be able to resize text up to 200% without
adverse effects (things being cut off, overlapping...".

If the page does not reflow properly, that can cause "things being cut off"
or "overlapping". I didn't say that 1.4.4 was *only* about reflow, but if
you don't reflow properly, you can cause 1.4.4 issues.

And since we don't know what "not usable" means in the original question, I
qualified by reply by saying it *could* be a 1.4.4 issue but without
further info, I can't say for sure.

From: wolfgang.berndorfer@zweiterblick.at
Date: Fri, Nov 29 2019 12:56PM
Subject: Re: 200% website scaling
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Hi specialists,

I’d interpreted 1.4.4. as:
a) Avoid horizontal scrolling for text (i.e. access reflow if possible).
b) Don’t cause overlapping up to 200% scaling.
Are there any further issues imaginable? Help me, if I’m wrong.

And what is substantially new in 1.4.10 more than the exceptions for very
small viewports?

I didn't even understand your distinction between display and accessibility
settings. Magnification tools in an OS or application are AT in my
interpretation. And both can cause the necessity of horizontal scrolling,
right as ZoomText does in the full screen magnification mode (Don't know the
exact English Terminology).

Thanks for clarifications and tutoring!

Wolfgang

-----Ursprüngliche Nachricht-----
Von: WebAIM-Forum < = EMAIL ADDRESS REMOVED = > Im Auftrag von glen
walker
Gesendet: Freitag, 29. November 2019 18:40
An: WebAIM Discussion List < = EMAIL ADDRESS REMOVED = >
Betreff: Re: [WebAIM] 200% website scaling

One of the great (and aggravating) things about accessibility is that some
issues are subjective.

> Not really. It's a display setting, not an accessibility setting.

As mentioned in my reply. "Make everything bigger" (scaling) is the "Ease of
Access" settings. Those are accessibility settings.

> Let's not confuse the matter by talking about reflow, which has
> nothing
to do with 1.4.4

Sure it does. You even said so yourself when you said "At any possible
viewport size, a user should be able to resize text up to 200% without
adverse effects (things being cut off, overlapping...".

If the page does not reflow properly, that can cause "things being cut off"
or "overlapping". I didn't say that 1.4.4 was *only* about reflow, but if
you don't reflow properly, you can cause 1.4.4 issues.

And since we don't know what "not usable" means in the original question, I
qualified by reply by saying it *could* be a 1.4.4 issue but without further
info, I can't say for sure.
http://webaim.org/discussion/archives

From: glen walker
Date: Fri, Nov 29 2019 1:37PM
Subject: Re: 200% website scaling
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>
> I’d interpreted 1.4.4. as:
> a) Avoid horizontal scrolling for text (i.e. access reflow if possible).
> b) Don’t cause overlapping up to 200% scaling.
>

I would be very careful about stating (a). All 1.4.4 says is that you
don't lose "content or functionality" when you zoom. It doesn't say that
you can't scroll. While you might have a design decision to prevent
horizontal scrolling, it is not required by 1.4.4

1.4.10 talks about scrolling (in addition to not losing "information or
functionality") but only says scrolling in two directions is discouraged
(with exceptions). If you had to scroll horizontally to view all the text
but didn't have to scroll vertically, that would pass 1.4.10.

From: Patrick H. Lauke
Date: Sat, Nov 30 2019 7:44AM
Subject: Re: 200% website scaling
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On 29/11/2019 17:40, glen walker wrote:
> One of the great (and aggravating) things about accessibility is that some
> issues are subjective.
>
>> Not really. It's a display setting, not an accessibility setting.
>
> As mentioned in my reply. "Make everything bigger" (scaling) is the "Ease
> of Access" settings. Those are accessibility settings.

It's also set in

System > Display > Scale and Layout

Not exclusively an "accessibility" related setting, but a display setting.

>> Let's not confuse the matter by talking about reflow, which has nothing
> to do with 1.4.4
>
> Sure it does. You even said so yourself when you said "At any possible
> viewport size, a user should be able to resize text up to 200% without
> adverse effects (things being cut off, overlapping...".
>
> If the page does not reflow properly, that can cause "things being cut off"
> or "overlapping". I didn't say that 1.4.4 was *only* about reflow, but if
> you don't reflow properly, you can cause 1.4.4 issues.

thing being cut off means they're cut off and you can't get to them.
think overflow:hidden in CSS.

The appearance of scrollbars, rather than reflow, is perfectly fine in
light of 1.4.4. See for instance the understanding doc
https://www.w3.org/WAI/WCAG21/Understanding/resize-text.html under
"Examples":

"A user uses a zoom function in his user agent to change the scale of
the content. All the content scales uniformly, and the user agent
provides scroll bars, if necessary."

This is exactly why there was a need for an additional 1.4.10 SC for reflow.

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke
http://flickr.com/photos/redux/ | http://redux.deviantart.com
twitter: @patrick_h_lauke | skype: patrick_h_lauke

From: wolfgang.berndorfer@zweiterblick.at
Date: Sun, Dec 01 2019 12:54PM
Subject: Re: 200% website scaling
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Thanks Glen and Patrick for explanations!

So is it correct to say:

a) If an element passes 1.4.10, it passes 1.4.4 (Reflow is a sufficient
technique to resize text properly up to 200% zoom).
b) Since both criteria are listed up under the same conformance level AA,
1.4.4 is only to be applied for the exceptions in 1.4.10. (Only these
exceptions need no reflow and therefore need mechanisms like scroll bars to
avoid overlapping.)

I'm not sure about b) since I still don't understand, why 1.4.4 considers
200% magnification and 1.4.10 400% pixel magnifications..

Wolfgang

-----Ursprüngliche Nachricht-----
Von: WebAIM-Forum < = EMAIL ADDRESS REMOVED = > Im Auftrag von
Patrick H. Lauke
Gesendet: Samstag, 30. November 2019 15:45
An: = EMAIL ADDRESS REMOVED =
Betreff: Re: [WebAIM] 200% website scaling

On 29/11/2019 17:40, glen walker wrote:
> One of the great (and aggravating) things about accessibility is that
> some issues are subjective.
>
>> Not really. It's a display setting, not an accessibility setting.
>
> As mentioned in my reply. "Make everything bigger" (scaling) is the
> "Ease of Access" settings. Those are accessibility settings.

It's also set in

System > Display > Scale and Layout

Not exclusively an "accessibility" related setting, but a display setting.

>> Let's not confuse the matter by talking about reflow, which has
>> nothing
> to do with 1.4.4
>
> Sure it does. You even said so yourself when you said "At any
> possible viewport size, a user should be able to resize text up to
> 200% without adverse effects (things being cut off, overlapping...".
>
> If the page does not reflow properly, that can cause "things being cut
off"
> or "overlapping". I didn't say that 1.4.4 was *only* about reflow,
> but if you don't reflow properly, you can cause 1.4.4 issues.

thing being cut off means they're cut off and you can't get to them.
think overflow:hidden in CSS.

The appearance of scrollbars, rather than reflow, is perfectly fine in light
of 1.4.4. See for instance the understanding doc
https://www.w3.org/WAI/WCAG21/Understanding/resize-text.html under
"Examples":

"A user uses a zoom function in his user agent to change the scale of the
content. All the content scales uniformly, and the user agent provides
scroll bars, if necessary."

This is exactly why there was a need for an additional 1.4.10 SC for reflow.

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke
http://flickr.com/photos/redux/ | http://redux.deviantart.com
twitter: @patrick_h_lauke | skype: patrick_h_lauke
http://webaim.org/discussion/archives

From: Patrick H. Lauke
Date: Sun, Dec 01 2019 2:24PM
Subject: Re: 200% website scaling
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On 01/12/2019 19:54, = EMAIL ADDRESS REMOVED = wrote:
> I'm not sure about b) since I still don't understand, why 1.4.4 considers
> 200% magnification and 1.4.10 400% pixel magnifications..

- Some low vision users need magnification that's above just 200%.
That's why 1.4.10 goes up to 400%
- Low vision users, particularly once zooming to 400%, will have more
trouble reading text comfortably if they have to scroll both
horizontally and vertically.

This is the core reason for 1.4.10.

- For 1.4.4, it's acceptable to have things needing horizontal and
vertical scrollbars (as long as things don't overlap/become unreachable.

Generally, if you pass 1.4.10 you're passing 1.4.4. But the opposite is
not always true.

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke
http://flickr.com/photos/redux/ | http://redux.deviantart.com
twitter: @patrick_h_lauke | skype: patrick_h_lauke

From: Detlev Fischer
Date: Mon, Dec 02 2019 12:26AM
Subject: Re: 200% website scaling
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And there is the possibility that at narrower viewport widths (e.g. when zooming in) text size is progressively reduced via CSS so you don’t reach 200% text size even when zoomed in to 400% (browser zoom).

> Am 01.12.2019 um 22:24 schrieb Patrick H. Lauke < = EMAIL ADDRESS REMOVED = >:
>
>
> Generally, if you pass 1.4.10 you're passing 1.4.4. But the opposite is not always true.

From: wolfgang.berndorfer@zweiterblick.at
Date: Mon, Dec 02 2019 2:10AM
Subject: Re: 200% website scaling
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Thanks Patrick,

FYI: I am a low vision user and remember the wrap-funcitonality in Zoomtext
for DOS, which perfectly suited to my needs 25 years ago. Now I copy longer
text into word and read it with 88pt which corresponds to 800%. And for easy
text, I just listen to my screen reader.

> - Some low vision users need magnification that's above just 200%. That's
why 1.4.10 goes up to 400%

So 1.4.4 is required when zooming up to 200% and 1.4.10 when zooming up
beyond that up to 400%?

> - Low vision users, particularly once zooming to 400%, will have more
trouble reading text comfortably if they have to scroll both horizontally
and vertically.

I would clarify: will have more *often* trouble

Wolfgang

-----Ursprüngliche Nachricht-----
Von: WebAIM-Forum < = EMAIL ADDRESS REMOVED = > Im Auftrag von
Patrick H. Lauke
Gesendet: Sonntag, 1. Dezember 2019 22:24
An: = EMAIL ADDRESS REMOVED =
Betreff: Re: [WebAIM] 200% website scaling

On 01/12/2019 19:54, = EMAIL ADDRESS REMOVED = wrote:
> I'm not sure about b) since I still don't understand, why 1.4.4
> considers 200% magnification and 1.4.10 400% pixel magnifications..

- Some low vision users need magnification that's above just 200%.
That's why 1.4.10 goes up to 400%
- Low vision users, particularly once zooming to 400%, will have more
trouble reading text comfortably if they have to scroll both horizontally
and vertically.

This is the core reason for 1.4.10.

- For 1.4.4, it's acceptable to have things needing horizontal and vertical
scrollbars (as long as things don't overlap/become unreachable.

Generally, if you pass 1.4.10 you're passing 1.4.4. But the opposite is not
always true.

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke
http://flickr.com/photos/redux/ | http://redux.deviantart.com
twitter: @patrick_h_lauke | skype: patrick_h_lauke
http://webaim.org/discussion/archives

From: Patrick H. Lauke
Date: Mon, Dec 02 2019 2:28AM
Subject: Re: 200% website scaling
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On 02/12/2019 09:10, = EMAIL ADDRESS REMOVED = wrote:
> So 1.4.4 is required when zooming up to 200% and 1.4.10 when zooming up
> beyond that up to 400%?

To be pedantic: due to a quirk in how it was written, 1.4.10 only
applies *at* the exact viewport sizes of 320 CSS px for vertical content
/ 256 CSS px for horizontal content

Zooming (using actual browser zoom) has the effect of changing the
browser's viewport CSS pixel measurements.

Some more discussion on this here https://github.com/w3c/wcag/issues/698

P
--
Patrick H. Lauke

www.splintered.co.uk | https://github.com/patrickhlauke
http://flickr.com/photos/redux/ | http://redux.deviantart.com
twitter: @patrick_h_lauke | skype: patrick_h_lauke