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Re: Notice of impending Formal Objection to Issue 30 Decision (@longdesc)

From: Laura Carlson <laura.lee.carlson@gmail.com>
Date: Thu, 12 Aug 2010 16:24:15 -0500
Message-ID: <AANLkTi=aeTpYYCuSBPPS4zm=2VsSu_tyD3hp8Jv3Eb4O@mail.gmail.com>
To: Janina Sajka <janina@rednote.net>
Cc: HTML Accessibility Task Force <public-html-a11y@w3.org>
Hi Janina

> We now find ourselves without a mechanism to do #2, unless we load up
> the page with the longer text. In other words, reference to an off-page
> description is a key requirement for proper functioning of the #2
> mechanism. With longdesc gone, so is our ability to do that.

I did discuss the lack of a functional replacement and the use case on
the survey [1] as did others to no avail:

<quote>
"HTML5 does not provide an equivalent or alternative mechanism. A
functional replacement does NOT currently exist as Chaals illuminated.
Use cases for longdesc and aria- describedby are related, but
significantly different that both should remain tools for content
authors...

Many images cannot be sufficiently described with other long
description techniques. For instance, longdesc currently provides a
solution for describing the content of pie and flow charts to the
blind when 1.) it would be not only visually apparent and redundant to
a sighted person but 2).) it would also be completely unacceptable to
the marketing department due to aesthetic considerations. There is
currently absolutely no other direct way of doing that without a
longdesc.

As Gez Lemon has further explained [2], aria-describedby does not
provide a functional replacement for longdesc. aria-describedby will
annotate text in the target id referenced by the idref. This means
assistive technology users would not be able to control how they
interact with the long description (as they can with longdesc). As, by
definition, a long description is in fact long, aria-describedby is
not good solution for a longdesc. Some future feature that that moves
the user's reading cursor to the longer description in a different
page where the user can control how they read the long description
could be a possible solution.

But some future version of aria-describedby is out of scope for this
decision. It does not exist. And even if some future version of
aria-describedby did provide the same functionality as longdesc, which
it currently does not, aria-describedby lacks browser support. IE 8,
Opera and Safari browsers on Windows do not support aria-describedby
[3]. It was recently announced that IE9 will not support
aria-describedby. [4]"
<unquote>

Best Regards,
Laura

[1] http://www.w3.org/2002/09/wbs/40318/issue-30-objection-poll/results#xkeepnew
[2] http://www.w3.org/2002/09/wbs/44061/200404_ftf-proposals/results#xq2
[3] http://www.paciellogroup.com/blog/aria-tests/aria-labelledby-input.html
[4] http://lists.w3.org/Archives/Public/wai-xtech/2010Jun/0020.html
Received on Thursday, 12 August 2010 21:24:44 UTC

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