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Re: Multiple H1 tags in an HTML5 web page

for

From: Steve Faulkner
Date: Mar 8, 2014 2:02AM

Hi all,

Jared is correct. There are no implementations of the outline algorithm in
browsers or other user agents and there is unlikely to be as there is no
requirements on user agents to implement it. There are a few 3rd party
implementations in JavaScript (demos) and one in XSLT in ePub. (this is
used to produce a table of contents for a book).

It will probably not be dropped from the spec as features are dropped when
they have implementation requirements but no implementations, this is not
the case for the outline algorithm (there are no requirements).

There are requirements on user agents to map heading levels in acc APIs
based on the headings outline depth
http://www.w3.org/html/wg/drafts/html/master/dom.html#sec-implicit-aria-semantics

These have not been implemented because they rely on the outline algorithm
being implemented (which is not a requirement and browser vendors have
shown no intention to implement) I am in the process of talking with
browser acc implementers to drop these requirements from the html spec.

this article may be helpful
http://blog.paciellogroup.com/2013/10/html5-document-outline/

The advice in the HTML
specification<http://www.w3.org/html/wg/drafts/html/master/sections.html#headings-and-sections>;is
clear on this:

Sections may contain headings of any rank, and authors are strongly
encouraged to use headings of the appropriate rank for the section's
nesting level.


ePub also advocates use of correct heading levels
http://www.idpf.org/accessibility/guidelines/content/xhtml/headings.php



--

Regards

SteveF
HTML 5.1 <http://www.w3.org/html/wg/drafts/html/master/>;


On 8 March 2014 02:37, Jared Smith < <EMAIL REMOVED> > wrote:

> Duff Johnson wrote:
> >> Of course this assumes that everything is done correctly
> >> and that the algorithm properly reflects the intended structure.
> > You make it sound as if this is all very unlikely. Is that fair?
>
> Considering the general abuse and mis-use of HTML5 sectioning elements
> (particularly <section>), I have seen very few instances where if the
> HTML5 outlining algorithm were applied it would result in improved
> accessibility.
>
> >> And there's a good chance this algorithm may change or be dropped from
> >> HTML5 entirely.
> >
> > Fascinating. How would one track this question?
> >
> > Also, if it was dropped from HTML5 how would that affect EPUB3?
>
> These are better questions for Steve Faulkner or others. I know that
> due to very limited implementations there has been some rumors of
> changing or dropping it.
>
> > Just to be clear: you are referring to HTML 4.01, which specifies <H1> -
> <H6>, right?
>
> Yes.
>
> > So, if the author needs to go deeper (H7, H8...) - which was actually
> the point of Greg's question - you are saying they out of luck?
>
> The answer to that question would be "yes". Greg was, I believe,
> instead referring to the fact that you could give each sectioning
> element its own independent heading structure beginning with an <h1>
> (or really any heading level for that fact) and the outline presented
> to the user would be 'reset' and adjusted to reflect a proper outline
> regardless of the heading levels actually used in markup. If fact, you
> could use <h1> for EVERY heading and just wrap each section in
> appropriately nested <section> elements - and this would result in a
> proper outline for the document, assuming the outlining mechanisms
> were actually implemented, which they presently are not.
>
> Here's a slide I've used that demonstrates that the heading levels
> used wouldn't really matter that much if the outlining mechanisms
> actually worked -
> http://webaim.org/presentations/2013/ariahtml5/sectionarticle3
>
> Jared
> > > >