XHTML Problems

[jp29]

My take on problems composing, serving and rendering XHTML
documents/web pages:

1. Typical conscientious web authors are producing XHTML documents (Web
pages) that feature valid Markup and with the content (MIME) type
specified as text/html
(http://keystonewebsites.com/articles/mime_type.php). These pages are
then loaded on to their Server where they are served to Rendering
Agents (browsers) as HTML (SGML application) documents with no problem
-- most Web Service Provider implementations associate HTML documents
with the content (MIME) type text/html. These pages are rendered
successfully by all extant graphical browsers -- but they are not XHTML
documents -- they are HTML documents without XML functionality
(http://hixie.ch/advocacy/xhtml). HTML documents that include DocType
declarations display in standards mode -- those that do not display in
"quirks (non-standard) mode. MSIE browsers render XHTML documents that
include the XML declaration in "quirks" mode, therefor, it seems the
declaration should be omitted for XHTML documents served as HTML --
although the W3C doesn't do so on their Home page.

2. Web authors who produce XHTML documents (Web pages) that feature
valid Markup and with the content (MIME) type specified as
application/xhtml+xml (prescribed by the W3C) inevitably face serious
problems (http://www.w3.org/International/arti...erving-xhtml/).
Most Web Service Provider implementations do not recognize this content
(MIME) type. In that event, the web author must contact his or her Web
Service Provider to try and convince them to adopt
application/xhtml+xml as the content (MIME) type to associate with
XHTML documents.If that doesn't work -- and it often doesn't -- then
the web author is faced with the task of producing and loading up to
the server a .htaccess file that provides the association -- a tricky
endeavor for many web authors. But the problems do not end there.
Current XML compliant browsers such as Mozilla, Netscape, Opera, et al.
retrieve and render these pages with no problem. However, older
browsers -- and more importantly by far -- the most frequently used
graphical browsers today -- MSIE 5.x/6.x -- will not render these
documents correctly. MSIE presents them as Down Load files and there is
no backward compatibility for older browsers
(http://www.w3.org/People/mimasa/test...-types/results)

3. This situation is a dilemma for web authors -- and the W3C. The W3C
has attempted to resolve this situation by installing a facility called
Content-Negotiation on their Server (to be a model for others?) that is
supposed to offer a choice of content (MIME) type text/html or
application/xhtml+xml XHTML documents to browsers so that they can
render them according to their capabilities
(http://www.w3.org/2003/01/xhtml-mime...t-negotiation). The
idea is to provide backward compatibility for older browsers and
accommodate current non XML compliant MSIE browsers. Of course, all
these would be HTML documents -- not XHTML documents. In theory, XML
compliant browsers would be served fully functional XHTML documents.
The W3C offers their Home page as an exemplar of this functionality.
BTW, the W3C Content Negotiation page only addresses the Apache Server
implementation in depth, Jigsaw only briefly and others such as Zeus
not at all.

4. The above procedure is not working for me. The page displays
correctly in my (XML compliant) Mozilla Firefox browser, but when I run
it through the W3C Markup validator the Content-Type displays as
text/html -- it is not being served as an XHTML document as intended.
Of course, if the W3C fix did work, the pages would still only be
served as HTML. It seems to me these problems must be sorted out ASAP
by the W3C -- certainly before they release XHTML 2.0. Now if only
Microsoft would produce a browser (and offer modifications to their
existing ones) to recognize content (MIME) type application/xhtml+xml
and serve real XHTML documents -- just like Firefox, Opera, et al. do!

James Pickering
Pickering Pages
http://www.jp29.org/

[Benjamin Niemann]

jp**@cox.net wrote:

My take on problems composing, serving and rendering XHTML
documents/web pages:

1. Typical conscientious web authors are producing XHTML documents (Web
pages) that feature valid Markup and with the content (MIME) type
specified as text/html
(http://keystonewebsites.com/articles/mime_type.php). These pages are
then loaded on to their Server where they are served to Rendering
Agents (browsers) as HTML (SGML application) documents with no problem
-- most Web Service Provider implementations associate HTML documents
with the content (MIME) type text/html. These pages are rendered
successfully by all extant graphical browsers -- but they are not XHTML
documents -- they are HTML documents without XML functionality
(http://hixie.ch/advocacy/xhtml). HTML documents that include DocType
declarations display in standards mode -- those that do not display in
"quirks (non-standard) mode. MSIE browsers render XHTML documents that
include the XML declaration in "quirks" mode, therefor, it seems the
declaration should be omitted for XHTML documents served as HTML --
although the W3C doesn't do so on their Home page.

2. Web authors who produce XHTML documents (Web pages) that feature
valid Markup and with the content (MIME) type specified as
application/xhtml+xml (prescribed by the W3C) inevitably face serious
problems (http://www.w3.org/International/arti...erving-xhtml/).
Most Web Service Provider implementations do not recognize this content
(MIME) type. In that event, the web author must contact his or her Web
Service Provider to try and convince them to adopt
application/xhtml+xml as the content (MIME) type to associate with
XHTML documents.If that doesn't work -- and it often doesn't -- then
the web author is faced with the task of producing and loading up to
the server a .htaccess file that provides the association -- a tricky
endeavor for many web authors. But the problems do not end there.
Current XML compliant browsers such as Mozilla, Netscape, Opera, et al.
retrieve and render these pages with no problem. However, older
browsers -- and more importantly by far -- the most frequently used
graphical browsers today -- MSIE 5.x/6.x -- will not render these
documents correctly. MSIE presents them as Down Load files and there is
no backward compatibility for older browsers
(http://www.w3.org/People/mimasa/test...-types/results)

3. This situation is a dilemma for web authors -- and the W3C. The W3C
has attempted to resolve this situation by installing a facility called
Content-Negotiation on their Server (to be a model for others?) that is
supposed to offer a choice of content (MIME) type text/html or
application/xhtml+xml XHTML documents to browsers so that they can
render them according to their capabilities
(http://www.w3.org/2003/01/xhtml-mime...t-negotiation). The
idea is to provide backward compatibility for older browsers and
accommodate current non XML compliant MSIE browsers. Of course, all
these would be HTML documents -- not XHTML documents. In theory, XML
compliant browsers would be served fully functional XHTML documents.
The W3C offers their Home page as an exemplar of this functionality.
BTW, the W3C Content Negotiation page only addresses the Apache Server
implementation in depth, Jigsaw only briefly and others such as Zeus
not at all.

4. The above procedure is not working for me. The page displays
correctly in my (XML compliant) Mozilla Firefox browser, but when I run
it through the W3C Markup validator the Content-Type displays as
text/html -- it is not being served as an XHTML document as intended.
Of course, if the W3C fix did work, the pages would still only be
served as HTML. It seems to me these problems must be sorted out ASAP
by the W3C -- certainly before they release XHTML 2.0. Now if only
Microsoft would produce a browser (and offer modifications to their
existing ones) to recognize content (MIME) type application/xhtml+xml
and serve real XHTML documents -- just like Firefox, Opera, et al. do!

AFAIK content negotiation is only an issue for XHTML 1.0 - XHTML 1.1 and up
are required to be served as application/xhtml+xml.

I don't see any issues here that the W3C should solve. IMHO it was a mistake
to recommend using XHTML served as text/html - as long as you (as a
webmaster) cannot assume that the majority of user agents parse it as XML
there is no point in using XHTML 1.0 at all (there are no real differences
between XHTML1.0 and HTML4.01).
If you want to use XHTML anyway, then it's the webmasters job to setup the
server correctly (or the software that generates dynamic pages). That's not
the W3C's job.

--
Benjamin Niemann
Email: pink at odahoda dot de
WWW: http://www.odahoda.de/

[David Dorward]

jp**@cox.net wrote:

(http://www.w3.org/2003/01/xhtml-mime...nt-negotiation) when I run it through the W3C Markup validator the Content-Type displays
as text/html
The markup validator does not appear to send an accept header... but then it
doesn't, IIRC, have a proper XML parser anyway.
It seems to me these problems must be sorted out ASAP
by the W3C -- certainly before they release XHTML 2.0.
You're welcome to download the source of the validator and offer a patch.
Now if only
Microsoft would produce a browser (and offer modifications to their
existing ones) to recognize content (MIME) type application/xhtml+xml
and serve real XHTML documents -- just like Firefox, Opera, et al. do!

Yes, well, GoogleBot, Safari, Konqueror, Links, Lynx, and W3M don't support
XHTML yet either AFAIK.

--
David Dorward <http://blog.dorward.me .uk/> <http://dorward.me.uk/>
Home is where the ~/.bashrc is

[Martin Honnen]

jp**@cox.net wrote:

Current XML compliant browsers such as Mozilla, Netscape, Opera, et al.
retrieve and render these pages with no problem.

XHTML as application/xhtml+xml supports improves but there are certainly
still problems, in particular as on the web you cannot expect any user
to show up with the latest versions of Opera and Mozilla. And half of
the Opera 7.xy releases for instance do not support script in
application/xhtml+xml documents. Or Mozilla does render the document but
compared to text/html document not incrementally which is quite a
shortcoming:
<http://www.mozilla.org/docs/web-developer/faq.html#xhtmld iff>

--

Martin Honnen
http://JavaScript.FAQTs.com/

[jp29]

I will relate my own experiences in experimenting with XHTML Web pages
served with W3C "recommende d practice" Content/MIME-type of
application/xhtml+xml .

Of course, just using the header Markup ..........

<meta http-equiv="Content-Type" content="applic ation/xhtml+xml;
charset=utf-8" />

........... in the header of a test XHTML page didn't do the job -- the
Header output via http://www.web-caching.com/showheaders.html showed
Content-Type: text/html in my Mozilla Firefox Browser. I called my Web
Service Provider to inquire if their Server (Zeus/3.4) recognized
MIME-type application/xhtml+xml to associate with XHTML documents. The
technician I spoke with informed me that only MIME-type text/html was
recognized for association with HTML documents -- they were unwilling
to modify their implementation and suggested I compose and load to the
Server an appropriate .htaccess file to add MIME-type
application/xhtml+xml to my directory -- he offered to walk me through
the procedure, but I knew how to do that so I proceeded on my own. I
did compose and load up to the Server the following .htaccess file
...........

AddType application/xhtml+xml html

...... That did the trick. I tested my exemplar XHTML 1.0 (strict) page
http://www.jp29.org/indexx.html in
http://www.web-caching.com/showheaders.html and the header showed
Content-Type: application/xhtml+xml in my Firefox Browser (of course
only a Download File window is rendered by MSIE 6.0). I use the file
extension .htm for my HTML pages and .html for my (experimental) XHTML
pages in order to use both MIME-types on my Server.

IMO http://www.wats.ca/resources/.htaccessandmimetypes/32 is an
excellent reference and guide for those XHTML authors who wish to
compose and load their own .htaccess file in order to add a required
MIME-type and are not familiar with the procedure.

James Pickering
Pickering Pages
http://www.jp29.org/

[Benjamin Niemann]

jp**@cox.net wrote:

[snip]
I use the file
extension .htm for my HTML pages and .html for my (experimental) XHTML
pages in order to use both MIME-types on my Server.

Why not use .html and .xhtml? At least on my local apache
installation .xhtml files are served as application/xhtml+xml - I guess
that this is the default, and probably for other servers, too.

--
Benjamin Niemann
Email: pink at odahoda dot de
WWW: http://www.odahoda.de/

[James Pickering]

Benjamin Niemann wrote:

........... Why not use .html and .xhtml? ..........

Laziness and convenience -- HTML-Kit (my Editor) uses .htm & html as
automatic file extensions.
........... my local apache installation .xhtml files are served as
application/xhtml+xml - I guess that this is the default, and probably
for other servers, too ..........

Not on my Web Service Provider Zeus 3.4 implementation -- the only
MIME-Type association they provide is text/html (for HTML).

James Pickering
http://www.jp29.org/

[David Dorward]

James Pickering wrote:

David Dorward wrote:

The markup validator does not appear to send an accept header

The extended interface does:
http://validator.w3.org/detailed.html

Nope. Just tested that too. Not sign of an accept header.

--
David Dorward <http://blog.dorward.me .uk/> <http://dorward.me.uk/>
Home is where the ~/.bashrc is

[James Pickering]

David Dorward wrote:

James Pickering wrote:

David Dorward wrote:

The markup validator does not appear to send an accept header

The extended interface does:
http://validator.w3.org/detailed.html

Nope. Just tested that too. Not sign of an accept header.

Try:

http://www.web-caching.com/showheaders.html

James Pickering
http://www.jp29.org/

[Henri Sivonen]

In article <da************ *******@news.de mon.co.uk>,
David Dorward <do*****@yahoo. com> wrote:

Yes, well, GoogleBot, Safari, Konqueror, Links, Lynx, and W3M don't support
XHTML yet either AFAIK.

Safari supports XHTML as application/xhtml+xml but does not advertise it
in the Accept header. I have not tried scripting with XHTML, though.

In the absence of an explicit character encoding declaration, Safari
fails to decode characters properly.

--
Henri Sivonen
hs******@iki.fi
http://hsivonen.iki.fi/
Mozilla Web Author FAQ: http://mozilla.org/docs/web-developer/faq.html