Using aria-hidden="false" on a descendant of an element with aria-hidden="true"does not expose that element. aria-hidden="true" hides itself and all its content from assistive technologies.
By adding aria-hidden="true" to an element, content authors ensure that assistive technologies will ignore the element. This can be used to hide parts of a web page that are pure decoration, such as icon fonts - that are not meant to be read by assistive technologies.
An element with an aria-hidden attribute set to true that is also part of the sequential focus navigation may cause confusion for users of assistive technologies because the element can be reached via sequential focus navigation, but it should be hidden and not included in the accessibility tree.
The 1 second time span introduced in the exception of the definition of focusable is an arbitrary limit which is not included in WCAG. Given that scripts can manage the focus state of elements, testing the focused state of an element consistently would be impractical without a time limit.
Assumptions
Interacting with the page does not result in changing the aria-hiddenattribute value of target elements. An example of such a situation would be when closing a modal dialog makes previously hidden elements that were not focusable or part of the sequential focus navigation become focusable and part of the sequential focus navigation.
Accessibility Support
Some user agents treat the value of aria-hidden attribute as case-sensitive.
This a element is not focusable because it moves focus to the input element whenever it receives focus. These elements
are sometimes referred to as 'focus sentinel' or 'bumper'. They are typically found before and after a modal / dialog in
order to contain focus within the modal. Page authors do not want the sentinel to be visible, nor do they want them to be read by
a screen reader. But, they do want the element to be part of the sequential focus navigation. This allows the page author
to detect that focus has left the dialog in order to wrap it to the top/bottom as appropriate.
<divid="sampleModal"role="dialog"aria-label="Sample Modal"aria-modal="true"style="border: solid black 1px; padding: 1rem;"
><label>First and last name <inputid="dialogFirst"/></label><br /><buttonid="closeButton">Close button</button></div><divaria-hidden="true"><ahref="#"id="sentinelAfter"style="position:absolute; top:-999em"
>Upon receiving focus, this focus sentinel should wrap focus to the top of the modal</a
>
</div><script>document.getElementById('sentinelAfter').addEventListener('focus', () => {
document.getElementById('dialogFirst').focus()
})
document.getElementById('closeButton').addEventListener('click', () => {
document.getElementById('sampleModal').style.display = 'none'
})
</script>
Passed Example 5
This button element is focusable, but not part of the sequential focus navigation because of the tabindex attribute.
This button element is part of the sequential focus navigation and a descendant of an element with an aria-hiddenattribute value of true because aria-hidden can't be reset once set to true on an ancestor.
This a element is focusable because it fails to move focus when it receives focus. This is in contrast to a focus sentinel that
immediately jumps focus to a valid location. Focus sentinels are typically used before and after a modal dialog in order to contain
and wrap focus. In this case, the focus event was removed, but the sentinel was not.
<divid="sampleModal"role="dialog"aria-label="Sample Modal"aria-modal="true"style="border: solid black 1px; padding: 1rem;"
><label>First and last name <inputid="dialogFirst"/></label><br /><buttonid="closeButton">Close button</button></div><divaria-hidden="true"><ahref="#"id="sentinelAfter"style="position:absolute; top:-999em"
>Upon receiving focus, this focus sentinel should wrap focus to the top of the modal</a
>
</div><script>document.getElementById('closeButton').addEventListener('click', () => {
document.getElementById('sampleModal').style.display = 'none'
})
</script>
Inapplicable
Inapplicable Example 1
This aria-hidden attribute is ignored with null value.
