Web Content Accessibility Guidelines a guide to the accessibility requirements
2 Operable

2.4.11 Focus Not Obscured (Minimum)

Conformance level: AA
Criterion released in WCAG version: 2.2

Official description of the success criterion

When a user interface component receives keyboard focus, the component is not entirely hidden due to author-created content.

What to do?

Ensure when an item gets keyboard focus, it is at least partially visible.

Why is it important?

People who can’t use a mouse need to see what has keyboard focus.

Common pitfalls

Having a modal positioned on the page so that it covers part of the content. If focus handling is not done correctly, it is possible that some interactive element is behind the modal and the focus style of it cannot be seen.

How to test for it?

Check the page and ensure that no element completely covers the interactive elements on the site.

More about this criterion elsewhere