Preselection behavior that preselects unaltered text in forms. When applied
to a certain component, the behavior is valid for all children of the
component. Therefore, it is possible to attach this behavior to any component,
well as to a form or even individual fields in a form. It is also possible to apply this
behavior to a page. The behavior applies
to text input fields and textareas. Upon focus, the text in the field is
selected if it it still identical to the default value.