Re: [orca-list] Feature request: Orca should support Aria-Hidden

[Joanmarie Diggs <jdiggs igalia com>]

Hi Eric.

On 12/23/2012 02:57 PM, Eric Scheibler wrote:
> Hello,
>
> currently I try to hide some content of a web site for screen
> readers. I only know one way to achieve that and this is the
> attribute aria-hidden="true". But sadly Orca ignores it and still
> reads the content.

Hmmmm. Is it Orca's job to "hide" this content, or the browser's?
Looking at the W3C's "WAI-ARIA 1.0 User Agent Implementation Guide"
[1], I see the following text:

<quote>
5.1.1. Excluding Elements from the Accessibility Tree

[...]

If not already excluded from the accessibility tree per the above
rules, user agents SHOULD NOT include the following elements in the
accessibility tree:

Elements, including their descendents, that have a WAI-ARIA global
attribute of aria-hidden="true". In other words, aria-hidden="true" on
a parent overrides aria-hidden="false" on descendants.
</quote>

So according to the W3C, it is the responsibility of "user agents" to
exclude the aria-hidden elements. So what is the definition of a "user
agent"? According to that same document, I read the following definitions:

<quote>
User Agent
Any software that retrieves, renders and facilitates end user
interaction with Web content.
</quote>

<quote>
Assistive Technologies
Hardware and/or software that:

* relies on services provided by a user agent to retrieve and render
  Web content
* works with a user agent or web content itself through the use of
  APIs, and provides services beyond those offered by the user agent to
  facilitate user interaction with web content by people with
  disabilities

[...]

Examples of assistive technologies that are important in the context
of this document include the following:

[...]

* screen readers, which are most-often used to convey information
  through synthesized speech or a refreshable Braille display;

[...]

</quote>

So according to the W3C's developer guide on ARIA, my conclusions are:

1. Orca, being a screen reader, is an assistive technology; not a user
   agent.
2. Firefox, being a web browser, is a user agent.
3. User agents, such as Firefox, should not expose objects with
   aria-hidden to screen readers such as Orca.
4. Sadly, apparently Firefox is failing to hide aria-hidden elements
   from Orca and as a result, Orca still reads the content.

Take care.
--joanie

[1] http://www.w3.org/WAI/PF/aria-implementation/