From c05786b00f8343cd5b7dffb36a79983246c1393a Mon Sep 17 00:00:00 2001 From: Scott O'Hara Date: Wed, 11 Sep 2024 11:08:40 -0400 Subject: [PATCH] Update index.html --- index.html | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/index.html b/index.html index 381f3723b..15a75e67d 100644 --- a/index.html +++ b/index.html @@ -11604,7 +11604,8 @@

Definitions of States and Properties (all aria-* attributes)

Indicates, when set to true, that an element and its entire subtree are hidden from assistive technology, regardless of whether it is visibly rendered.

User agents determine an element's [=element/hidden=] status based on whether it is rendered, and the rendering is usually controlled by CSS. For example, an element whose display property is set to none is not rendered. An element is considered [=element/hidden=] if it, or any of its ancestors are not rendered or have their aria-hidden attribute value set to true.

Authors MAY, with caution, use aria-hidden to hide visibly rendered content from assistive technologies only if the act of hiding this content is intended to improve the experience for users of assistive technologies by removing redundant or extraneous content. Authors using aria-hidden to hide visible content MUST ensure that identical or equivalent meaning and functionality is exposed to assistive technologies. Whenever possibe it's strongly recommended authors use host language features to exclude elements from the accessibility tree.

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Additionally, authors SHOULD ensure that any elements that are accessibility descendants of an aria-hidden element, or any elements which have been marked as aria-hidden themselves, are prevented from receiving focus. If an aria-hidden element or a descendant of an aria-hidden ancestor receives focus, User Agents MUST ignore the aria-hidden state of any ancestor to the focused element from that point forward, resulting in the entire subtree to be exposed to assistive technologies. The ancestor aria-hidden markup will continue to be ignored, even once the element loses focus or is no longer focusable.

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Additionally, authors SHOULD ensure that any elements that are accessibility descendants of an aria-hidden element, or any elements which have been marked as aria-hidden themselves, are either prevented from receiving focus, or upon receiving focus use scripting to immediately move focus to another element.

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User Agents MUST ignore the aria-hidden state of any ancestor to the focused element from that point forward, resulting in the entire subtree to be exposed to assistive technologies. The ancestor aria-hidden markup will continue to be ignored, even once the element loses focus or is no longer focusable. User agents MAY provide console messages to warn or flag aria-hidden errors to developers.

Authors are advised to use extreme caution and consider a wide range of disabilities when hiding visibly rendered content from assistive technologies. For example, a sighted, dexterity-impaired individual might use voice-controlled assistive technologies to access a visual interface. If an author hides visible link text "Go to checkout" and exposes similar, yet non-identical link text "Check out now" to the accessibility API, the user might be unable to access the interface they perceive using voice control. Similar problems can also arise for screen reader users. For example, a sighted telephone support technician might attempt to have the blind screen reader user click the "Go to checkout" link, which they might be unable to find using a type-ahead item search ("Go to…").

As of ARIA 1.3, aria-hidden="false" is now synonymous with aria-hidden="undefined".

The original intent for aria-hidden="false" was to allow user agents to expose content that was otherwise hidden from the accessibility tree. However, due to ambiguity in the specification and inconsistent browser support for the false value, the original intent is no longer supported.