Read-only if
The property read-only if determines whether an element is read-only or not.
If only one state or one user group has been selected, the form field can only be filled out, clicked at, or selected when the form is not in the selected state, or the user currently signed in is not a member of this group. For each state and user group there is also the opposite option to make a form element read-only when it is not in the selected state or not viewed by the selected user group.
When both a state and a user group are selected, the form field item can only be filled out, clicked at, or selected when the form is both not in the selected state and the user currently signed in does not belong to the selected user group as well.