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Re: meta refresh (3.7.5.3. Pragma directives)

From: Ben Boyle <benjamins.boyle@gmail.com>
Date: Wed, 8 Aug 2007 00:49:20 +1000
Message-ID: <5f37426b0708070749w1b4cc81u71cc0341ab1b6b1@mail.gmail.com>
To: "Anne van Kesteren" <annevk@opera.com>
Cc: "HTML WG" <public-html@w3.org>

That could be addressed through the kiosk (custom browser
functionality). I'm assuming you mean refresh while idle; if not I
don't see how it is exempt from the issues identified in WCAG.

I'm not finding the kiosk use case very compelling personally. I'm not
sure HTML is a good solution at all - there's flash and smil, animated
graphics, video... all manner of multimedia support besides "refresh"
(and not all requiring javascript). I assume there are other use cases
too, however I don't believe there would be priority 2 checkpoints in
WCAG without good reason. I trust WCAG.

WCAG explicitly include both refresh (7.4) and redirect (7.5):
http://www.w3.org/TR/WCAG10-CORE-TECHS/#auto-page-refresh
(I appreciate the advice I copied around HTTP is not applicable to
refresh scenarios!)

It's still in WCAG 2.0 too, although priority may be reduced (AAA = P3?).
http://www.w3.org/WAI/WCAG20/quickref/20070517/Overview.php#consistent-behavior-no-extreme-changes-context

It concerns me that W3C is drafting two documents, WCAG 2 saying
"don't use refresh" whilst HTML5 says "here's how to use refresh".
It's a contradiction and it causes problems, particularly when working
with third parties and managing contracts involving these specs that
result in long pointless debates with suppliers over what's acceptable
practice. It does not help if W3C publishes conflicting advice. But it
is managable - I am just explaining my "use case".

I have had to request too many suppliers (hosting partners,
application vendors, etc.) use HTTP redirections instead of
meta@refresh (and javascript location.href assignments) to support the
inclusion of this element in HTML5 (even for kiosks).


On 8/8/07, Anne van Kesteren <annevk@opera.com> wrote:
> On Tue, 07 Aug 2007 16:18:52 +0200, Ben Boyle <benjamins.boyle@gmail.com>
> wrote:
> > http://dev.w3.org/html5/spec/Overview.html#refresh
> >
> > WCAG is very clear that meta@refresh is bad practice. I believe we
> > should deprecate this in HTML5 and provide advice that is aligned with
> > the W3C accessibility initiative, namely:
> >
> >    1. Configure the server to use the appropriate HTTP status code
> > (301). Using HTTP headers is preferable because it reduces Internet
> > traffic and download times, it may be applied to non-HTML documents,
> > and it may be used by agents who requested only a HEAD request (e.g.,
> > link checkers). Also, status codes of the 30x type provide information
> > such as "moved permanently" or "moved temporarily" that cannot be
> > given with META refresh.
> >    2. Replace the page that would be redirected with a static page
> > containing a normal link to the new page.
> >
> > http://www.w3.org/TR/WCAG10-CORE-TECHS/#auto-page-refresh
>
> This addresses redirects, not refreshes. The use cases for refreshes from
> the WHATWG list if I remember correctly are pages to be shown in a kiosk,
> stock pages that don't want to rely on JavaScript being enabled, etc.
> Can't seem to find the discussion in the archives though.
>
>
> --
> Anne van Kesteren
> <http://annevankesteren.nl/>
> <http://www.opera.com/>
>
Received on Tuesday, 7 August 2007 14:49:28 GMT

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