Get Accessibility Properties by spectranaut · Pull Request #1960 · w3c/webdriver

spectranaut · 2026-05-12T00:44:08Z

Added/update sections:

To dos:

Definition of get a known accessible object could parallel get a know element. That is a long, branch algorithm, that will mean adding new parallel errors, and maybe even data structures. Should it eventually hook into existing data structures, like https://pr-preview.s3.amazonaws.com/Igalia/webdriver/pull/1960.html#dfn-node-id-map, or should it forever be separate?
- Some discussion of ids in comment on the Explainer.
Probably the algorithm for Element's Get Computed Properties is too vague about how to get the accessibility node.
Error handling
- Discussion on errors in explainer
Maybe expand on definition of accessibility id
- Discussion on IDs in the explainer

This change is

cookiecrook · 2026-05-21T17:18:13Z

+ <tr>
+  <td><dfn>stale accessible reference</dfn>
+  <td>404
+  <td><code>stale accessible reference</code>


Do we have confidence that the implementations will retain the difference between “was here but is now stale” and “not found for some other reason”? If not, the first 404 may suffice.

cookiecrook · 2026-05-21T17:24:05Z

+
+<p> An <dfn>accessibility ID</dfn> is a string value representing a handle to an <a>accessible object</a> in a specific WebDriver session.
+
+<p> <dfn>Accessibility properties</dfn> is a JSON <a>Object</a> that contains the relevant <a>WAI-ARIA states and properties</a> of an <a>accessible object</a>, as well as the following properties:


Not to downgrade ARIA, but it’s a subset here:

Suggested change

<p> <dfn>Accessibility properties</dfn> is a JSON <a>Object</a> that contains the relevant <a>WAI-ARIA states and properties</a> of an <a>accessible object</a>, as well as the following properties:

<p> <dfn>Accessibility properties</dfn> is a JSON <a>Object</a> that contains the relevant <a>accessibility properties</a> of an <a>accessible object</a>, as well as the following properties:

This suggestion is a bit tautological :)

I wonder if we should defined "computed accessibility properties" like we defined "computed role" in core-aam, and reference that...?

From he API meeting yesterday, this will likely land in either Core-AAM as a formalized property list... Most will reference ARIA attribute concepts, but some, like size/bounds, ignored (maybe), clickable, etc. may be specified in Core-AAM or another relevant AAM.

cookiecrook · 2026-05-21T17:28:10Z

+   <dd>The <a>accessibility ID</a> of the parent of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.
+
+   <dt>"<code>children</code>"
+   <dd>A list of <a>accessibility IDs</a> representing the children of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.


Suggested change

<dd>A list of <a>accessibility IDs</a> representing the children of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.

<dd>A list of <a>accessibility IDs</a> representing the child nodes of this <a>accessible node</a> in the implementation’s <a>accessibility tree</a>.

I think we need a term for the implementation's accessibility tree that is not "accessibility tree", maybe "internal accessibility tree" or "computed accessibility tree", because "accessibility tree" alone is defined in ARIA and it basically means the platform API's tree.

cookiecrook · 2026-05-21T17:31:06Z

+   <dd>A list of <a>accessibility IDs</a> representing the children of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.
+  </dl>
+
+<p> <dfn>Ignored accessible objects</dfn> are accessible objects that represent <a>elements which are excluded from the accessibility tree</a>. The <a>accessibility properties</a> of these <a>accessible objects</a> must only have the keys <va>accessibilityID</var>, <va>parent</var>, <va>children</var> and <va>role</var> set to <code>"none"</code>.


Ignored accessible children may not be implementable as written. The “ignored” state is usually on the non-accessibility rendered object which can—modulo implementation details—result in no backing accessibility node to return in the child list.

good point, I think we don't need this definition using your definition above.

cookiecrook · 2026-05-21T17:32:37Z

+<p>To <dfn>get a known accessible object</dfn> given <var>session</var> and <var>reference</var>:
+
+<ol class="algorithm">
+  <li><p>TO DO: Should we create a parallel to the specification of <a>get a known element</a>? Do we need to make a parallel structure to <a>browsing context group node map</a> and <a>node id map</a>?


I don’t think we need it, unless the element ID can’t be returned in the property bag.

cookiecrook · 2026-05-21T17:35:05Z

   <p>The following terms are defined
     in the Accessible Rich Internet Applications (WAI-ARIA) 1.2 specification: [[wai-aria-1.2]]
     <ul>
+       <li><dfn><a href="https://w3c.github.io/aria/#dfn-accessible-object"></a>accessible object</dfn>


Ditto node?

Maybe we should sync an ARIA edit with this PR?

Right so I originally used "accessible object" everywhere because that is defined in aria and "accessibility node" is not defined anywhere. But given your other comments... I'm realizing we can't define things in terms of ARIA's "accessibility tree" because that (and "accessibility object") is defined in terms of the platform accessibility API. And we are talking about something else, here.

To discuss in next week's API sync with @jcsteh et al.

cookiecrook · 2026-05-21T17:37:29Z

+       <li><dfn><a href="https://w3c.github.io/aria/#accessibility_tree">accessibility tree</a></dfn>
+       <li><dfn><a href="https://w3c.github.io/aria/#tree_exclusion">elements which are excluded from the accessibility tree</a></dfn>
       <li><dfn><a href="https://w3c.github.io/aria/#introroles">WAI-ARIA role</a></dfn>
+       <li><dfn><a href="https://w3c.github.io/aria/#introstates">WAI-ARIA states and properties</a></dfn>


We’ll need a landing spot for the new “accessibility properties” ref above because this ARIA list is a subset.

spectranaut

First pass at fixes to your comments, @cookiecrook, but I still need to work on definitions and where they belong!

spectranaut · 2026-05-26T22:35:51Z

+
+<p> An <dfn>accessibility ID</dfn> is a string value representing a handle to an <a>accessible object</a> in a specific WebDriver session.
+
+<p> <dfn>Accessibility properties</dfn> is a JSON <a>Object</a> that contains the relevant <a>WAI-ARIA states and properties</a> of an <a>accessible object</a>, as well as the following properties:


This suggestion is a bit tautological :)

I wonder if we should defined "computed accessibility properties" like we defined "computed role" in core-aam, and reference that...?

spectranaut · 2026-05-26T22:38:17Z

+   <dd>A list of <a>accessibility IDs</a> representing the children of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.
+  </dl>
+
+<p> <dfn>Ignored accessible objects</dfn> are accessible objects that represent <a>elements which are excluded from the accessibility tree</a>. The <a>accessibility properties</a> of these <a>accessible objects</a> must only have the keys <va>accessibilityID</var>, <va>parent</var>, <va>children</var> and <va>role</var> set to <code>"none"</code>.


good point, I think we don't need this definition using your definition above.

spectranaut · 2026-05-26T22:39:32Z

+   <dd>The <a>accessibility ID</a> of the parent of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.
+
+   <dt>"<code>children</code>"
+   <dd>A list of <a>accessibility IDs</a> representing the children of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.


I think we need a term for the implementation's accessibility tree that is not "accessibility tree", maybe "internal accessibility tree" or "computed accessibility tree", because "accessibility tree" alone is defined in ARIA and it basically means the platform API's tree.

spectranaut · 2026-05-26T22:45:19Z

   <p>The following terms are defined
     in the Accessible Rich Internet Applications (WAI-ARIA) 1.2 specification: [[wai-aria-1.2]]
     <ul>
+       <li><dfn><a href="https://w3c.github.io/aria/#dfn-accessible-object"></a>accessible object</dfn>


Right so I originally used "accessible object" everywhere because that is defined in aria and "accessibility node" is not defined anywhere. But given your other comments... I'm realizing we can't define things in terms of ARIA's "accessibility tree" because that (and "accessibility object") is defined in terms of the platform accessibility API. And we are talking about something else, here.

Get Accessibility Properties

82d7844

cookiecrook reviewed May 21, 2026

View reviewed changes

cookiecrook mentioned this pull request May 22, 2026

WebDriver: Add support for GetAccessibilityPropertiesForElement, GetAccessibilityPropertiesForAccessibilityNode commands WebKit/WebKit#65058

Draft

Accessible object to accessibility node and other fixes

71d6ead

spectranaut commented May 26, 2026

View reviewed changes

cookiecrook mentioned this pull request May 29, 2026

Redundancy with the accessibility tree webmachinelearning/webmcp#91

Open


		<p> An <dfn>accessibility ID</dfn> is a string value representing a handle to an <a>accessible object</a> in a specific WebDriver session.

		<p> <dfn>Accessibility properties</dfn> is a JSON <a>Object</a> that contains the relevant <a>WAI-ARIA states and properties</a> of an <a>accessible object</a>, as well as the following properties:

	<dd>A list of <a>accessibility IDs</a> representing the children of this <a>accessible object</a> in the <a>accessibility tree</a>, including <a>ignored accessible objects</a>.
	<dd>A list of <a>accessibility IDs</a> representing the child nodes of this <a>accessible node</a> in the implementation’s <a>accessibility tree</a>.

Conversation

spectranaut commented May 12, 2026 • edited by pr-preview Bot Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

cookiecrook May 21, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

spectranaut left a comment

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

spectranaut commented May 12, 2026 •

edited by pr-preview Bot

Loading

cookiecrook May 21, 2026 •

edited

Loading