How should focus be managed when opening and closing modal dialogs?

• A. Allow focus to move anywhere even when modal is open.
• B. Trap focus within the modal while open, return focus to the triggering element on close, and restore prior focus order when dismissed.
• C. Focus should skip the modal and go to background content.
• D. Closing a modal should never return focus.

Answer: (B)

When a modal opens, focus must be confined to the dialog itself so keyboard users can complete the task without accidentally interacting with content behind it. This focus trapping prevents tabbing to elements outside the modal and keeps the user’s attention on the dialog, which is crucial for accessibility and predictable behavior. When the user closes the modal, the focus should be returned to the element that opened it (the triggering control) and the prior focus sequence should be restored so the user can continue from where they left off. This combination ensures a clear, usable flow for both keyboard and assistive technology users. Allowing focus to roam the background, or skipping the modal, or never returning focus would break the expected modal behavior and create a confusing experience.