Understanding Success Criterion 2.4.12: Focus Not Obscured (Minimum)

Success Criterion 2.4.12 Focus Not Obscured (Minimum) (Level AA): When a user interface component receives keyboard focus, the component is not entirely hidden due to author-created content.

Status

This understanding document is part of the draft WCAG 2.2 content. It may change or be removed before the final WCAG 2.2 is published.

Intent

For sighted people with mobility impairments who use a keyboard-like device (e.g., a switch, voice input), knowing the current point of focus is very important. When progressing through a page other content can hide the focused element.

Where other content can overlap with a focused item, the focused element should not be hidden. Typical types of content that can overlap focused items are sticky footers, sticky headers, or non-modal dialogues. As a user tabs through the page, these layers of content can obscure the focused item, including the focus indicator. If the interface is configurable so that the user can move toolbars and non-modal dialogs around, then only the initial positions of user-movable content would be considered for testing and conformance of this success criterion.

Benefits

Examples

Techniques

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Sufficient Techniques

  1. CSS: Using scroll-padding to ensure a sticky header does not obscure the focused item (Potential future technique).

Failures

The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group.

Key Terms

user interface component

a part of the content that is perceived by users as a single control for a distinct function

Note

Multiple user interface components may be implemented as a single programmatic element. "Components" here is not tied to programming techniques, but rather to what the user perceives as separate controls.

Note

User interface components include form elements and links as well as components generated by scripts.

Note

What is meant by "component" or "user interface component" here is also sometimes called "user interface element".

An applet has a "control" that can be used to move through content by line or page or random access. Since each of these would need to have a name and be settable independently, they would each be a "user interface component."