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Re: 48-Hour Consensus Call: InstateLongdesc CP Update

From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Date: Mon, 24 Sep 2012 14:22:25 +0200
To: Charles McCathie Nevile <chaals@yandex-team.ru>
Cc: Laura Carlson <laura.lee.carlson@gmail.com>, Silvia Pfeiffer <silviapfeiffer1@gmail.com>, Geoff Freed <geoff_freed@wgbh.org>, HTML Accessibility Task Force <public-html-a11y@w3.org>
Message-ID: <20120924142225435011.d8e94549@xn--mlform-iua.no>
Charles McCathie Nevile, Mon, 24 Sep 2012 12:58:55 +0200:
> On Sun, 23 Sep 2012 02:41:56 +0200, Silvia Pfeiffer wrote:
>> the vast pollution of @longdesc values […] would be replaced by
>> only clean and accurate use of @aria-describedat

> factors that […] will lead to aria-describedat having […] pollution:
> 3. Longdesc isn't terribly complicated. The original description of 
> longdesc for img begins:
> "This attribute specifies a link to a long description of the image. 
> This description should supplement the short description provided 
> using the alt attribute..."
> While it isn't a perfectly clear specification, I found it difficult 
> to understand how reading it could lead to any major confusion.

I believe most of the the misused @longdesc attributes points to an 
image. And that authors’ need for an extra image URL attribute, 
'creative', self-forgiving 'read-my-wish-into-the-standard' in 
combination the fact that HTML4/XHTML1 is DTD-based and their 
validation is DTD-based too (per the DTD, any URL is valid!) - in 
combination with lack of browsers where @longdesc is implemented in a 
way that ordinary authors can experience, is largely what has lead us 
to where we are.[1] The following quote from someone who is fully aware 
of HTML5, demonstrates how the reasoning goes: [2]

   jQuery Fullsize Plug-in [ … ] Since there is no fullsize attribute 
for the <IMG> tag yet, I am using the longdesc attribute instead. 
longdesc is a completely valid image attribute and is meant to contain 
a URL to a description of the image. The Fullsize jQuery plug-in is 
super easy to use, and provides a kick start to standardizing the way 
image pop-ups look and work.

If @aria-describedAT does not suffer the same, severe destiny, then it 
will be because:

 * HTML5 is more extensible than XHTML1/HTML4 (read: @data-foo="") 
   so the need is not as great.
 * the move away from DTD-based spec and DTD-based validation makes
   it more difficult and less credible to fake
 * may be it becomes simpler to test A11Y?

If HTML5 gained the @fullsize attribute, as well, then that would help, 
too. Alas.[3]

[1] http://lists.w3.org/Archives/Public/public-html-a11y/2012Sep/0423

[2] http://www.addfullsize.com

[3] https://www.w3.org/Bugs/Public/show_bug.cgi?id=12365#c11

leif halvard silli
Received on Monday, 24 September 2012 12:23:03 UTC

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