I have cross references in headers of a multi-section document that I need
to update after a change. I can update them one at a time by right clicking
and hitting "Update Field" but I can't figure out how to globally update all
cross references in the entire document. I can only select info in the
section I'm in. All of the other sections' headers remain unchanged.

Is it possible to select info in all section headers in one shot so that I
can update all of the cross references in the whole document?