Keyboard trap

A keyboard trap occurs when a user navigating with the keyboard from a position on the screen (e.g. a form field, a button, a complex component) cannot reach the next or previous component.

There are special cases where it is necessary to capture the keyboard focus and prevent the user from reaching the elements following or preceding the element currently being viewed. For example, in a modal window it is imperative that the user navigating with the keyboard cannot reach components outside the modal window as long as the latter is active.