- From: Ian Jacobs <ij@w3.org>
- Date: Wed, 19 Jul 2000 16:30:01 -0400
- 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 UTC