Is there a way to collapse all the headings in the doc pane at one time. At present, one has to go through and collapse one heading after another. If one could collapse them all at one time, this would really enhance the usefulness of expand/collapse in the doc pane. As it is, if one wants to, say,  search for a word, one may need to expand all the headings. But then, if one has makes any changes, one has to tediously collapse one heading after another.