It just won't go away! I can't find anything on the menus to get rid of it. It blocks the view of whichever document I'm trying to read. What's odd is that when I first opened a PDF document, it looked just fine; but subsequent openings of the same document had that right-hand column blocking about one-fourth of the document, requiring horizontal scrolling. Who can be bothered? Please tell me this is an easy fix. Thank you!