SIA-R84Scrollable elements are keyboard accessible

Accessibility requirements

This rule tests conformance of the following accessibility requirements:

Description

This rule checks that scrollable elements can be scrolled by keyboard.

Applicability

Any element in the HTML namespace that has visible children in the flat tree for which one of the following is true:

It has a horizontal scroll distance greater than the computed left or right padding of the element; or
It has a vertical scroll distance greater than the computed top or bottom padding of the element

Expectations

The test target has an inclusive descendant in the flat tree that is included in sequential focus navigation.

Focus must be on or in a scrollable region, to ensure there is some element from which arrow keys can be used to control the scroll position. This can still create an issue if scripts are used to prevent the keyboard events from reaching the scrollable region. This must be tested separately.

Assumptions

This rule assumes that all scrollable elements with visible content need to be keyboard accessible. Scrollable elements that do not need to be keyboard accessible, perhaps because their content is purely decorative or because scroll can be controlled some other way, may fail this rule but still satisfy success criterion 2.1.1 Keyboard.

Accessibility support

This rule has no known accessibility support concerns.