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Proposed modification to checkpoint 2.7 (identification of language)

From: Ian Jacobs <ij@w3.org>
Date: Wed, 19 Jul 2000 16:30:01 -0400
Message-ID: <39760FC9.897C1A20@w3.org>
To: w3c-wai-ua@w3.org
Hello,

In the 7 July UA Guidelines, checkpoint 2.7 reads:

  2.7 For author-identified but unsupported natural 
      languages, allow the user to configure the user 
      agent to identify those language changes in content.

At the 13 July teleconference [2], I expressed a concern about
proposing the minimal requirement be to render the information
"in content" and got an action item to propose a change.
Please consider the following proposals:

1) Delete checkpoint 2.7. This checkpoint was initially 
   included in the UA Guidelines in support of the WCAG 1.0 
   checkpoint 4.1:

       Clearly identify changes in the natural language of a 
       document's text and any text equivalents (e.g., captions).

   As I recall, this checkpoint was included as a P1 requirement
   to that screen readers capable of handling several languages might
   switch dictionaries. However, checkpoint 2.7 is not about making
   the markup provided by the author available to assistive
technologies;
   it's abount rendering through the native UI. In my opinion,
   our requirements to implement the DOM are the appropriate 
   reflection of the WCAG 1.0 requirement. And therefore, if the
   checkpoint is not about the UI, I think we should delete it.

2) Don't delete checkpoint 2.7 because rendering content written in
   an unsupported natural language with incomprehensible glyphs or
   sounds may cause accessibility problems. I don't think we should
argue
   that the problems are for assistive technologies (since they should
get
   the information through the DOM). But we could argue for that many
   users, including users with some disabilities, viewing content
through
   a native viewport when that content is rendered as garbage may be
   disorienting. We should either require the UA not to render garbage,
   or to identify it as such. 

   I would note that the HTML specification, section 5.4 [5] discusses
   the handling of undisplayable characters. It recommends the following
   to user agents:

      Adopt a clearly visible, but unobtrusive mechanism to 
      alert the user of missing resources. 

  Please consider the following wording for a revised P3 checkpoint:

  <NEW>
    2.7 For content in a recognized but unsupported natural 
        language, allow configuration so that when rendered,
        this content does not disorient the user. The user 
        agent may choose to not render this content, but must
        indicate the absence through the user interface.
      Note: For example, if the user agent does not support
      Japanese, render "[Japanese text]" instead of the content,
      or use an accessible icon that indicates an unsupported language.
   </NEW>

Other techniques:

 - Render the name of the language and use a colored background
   to indicate that content is garbage.

Notes:

 - I have removed the part about the text being marked-up
   by the author. I think the requirement should apply for
   any text content recognized by the user agent as being
   in an unsupported natural language. The techniques document
   talks about ways to identify natural language.

 - The requirement used to only be about changes in natural language.
   However, I think the accessibility issue raised above applies
   for all unsupported natural languages, even if the entire document
   is in that language.

   IMPORTANT: We decided (refer ot issue 174) to remove a requirement
   to render content according to natural language specifications
because
   we said that not doing so was not an accessibility issue. I'm arguing
   here that rendering junk without warning the user that it's junk
   may be an accessibility issue.

 - Ian

[1] http://www.w3.org/WAI/UA/WD-UAAG10-20000707/
[2] http://lists.w3.org/Archives/Public/w3c-wai-ua/2000JulSep/0056.html
[3] http://lists.w3.org/Archives/Public/w3c-wai-ua/2000AprJun/0448.html
[4] http://www.w3.org/TR/1999/WAI-WEBCONTENT-19990505
[5] http://www.w3.org/TR/1999/REC-html401-19991224/charset.html#h-5.4
[6] http://cmos-eng.rehab.uiuc.edu/ua-issues/issues-linear.html#174
-- 
Ian Jacobs (jacobs@w3.org)   http://www.w3.org/People/Jacobs
Tel:                         +1 831 457-2842
Cell:                        +1 917 450-8783

Received on Wednesday, 19 July 2000 16:30:02 GMT

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