If I try customizing my toolbars to put my bookmarks toolbar on the bottom, it disappears. While disappearred, if I uncheck the View > Toolbars then the 2nd to last row disappears (which is my location bar and Google search bar). In the Customize view, the space where the Bookmark toolbar reappears there, but it shrinks away to three rows once I leave the Customize View. I can move the Bookmark toolbar to other locations and it won't disappear. It just doesn't like being on the bottom. It doesn't seem to like being pushed into four rows.