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Re: "Overlay" accessibility products.

for

From: Birkir R. Gunnarsson
Date: Mar 26, 2019 9:12AM

There is a website dedicated to this questions (the site is called
"Overlays don't work")
https://overlaysdontwork.com/


I'm a bit more pragmatic personally but I agree wit the basic premise of this.
Firstly, implementing an overlay is expensive, you have to have a
vendor do a full accessibility assessment and write the solution.
Secondly overlays are brittle, if you change anything in the
underlying code you must adjust the overlay. Most websites are living
things that get updated sometimes even daily, that could be a heck of
a lot of overlay updates, each of which is going to be costly.
Thirdly, overlays can present a security vulnerability (depending on
how the JavaScript is linked).
Forthly, an overlay that, e.g. reads the website out loud or enables
the user to adjust contrast does not make the site accessible. I think
these could be useful for certain groups of users in certain
circumstances, so you can offer them as extras but they do not make
the site accessible, only conformant and valid code does.
Finaly, I"ve seen some overlays that make the site worse. There are
some vendors out there who don't have a clue what they're doing (there
are overlays from trusted vendors as well), f iif you are to purchase
an overlay be careful who is offering I.

For a static site and as a short-term solution I can see an overlay as
a possibility. For any other type of site it tends to be a pricy and
ineffective.

Accessibility testing tools that validate the DoM (most tools do)
would detect overlay fixes (the fixes are processed by the browsers
and made available in the DOM).



On 3/26/19, Fix, Lawrence < <EMAIL REMOVED> > wrote:
> I'm interested in opinions about accessibility products that "overlay" a web
> site providing an accessible view of the site, without changing the code of
> the site. Do they truly make your site compliant? I believe that automated
> testing tools will still detect errors when crawling the code. Is that OK
> as long as the user can use the site?
>
> Thanks!
>
> Larry Fix
> AIG
> Web Site Accessibility
> L&R Experience Design
> 80 Pine St, New York, NY 10005
> Tel +1 917 703 3916
> <EMAIL REMOVED> | www.aig.com
>
> > > > >


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