One important caveat: If someone can see your document, they can copy it. All you are doing with any Word protection is making copying more difficult. Like most house keys, it helps keep honest people honest.

If the restriction is for Filling in Forms, all that can be selected is formfield contents and content control contents. If you restrict it to "No Changes - with exceptions" other parts which cannot be edited can still be selected (highlighted in your terms) and copied.

Filling in Forms protection has its own set of problems.