code: function(){
            var part = this.get();
            // Allow empty nodes when they are alone on a line, needed
            // for the FF cursor bug workaround (see select.js,
            // insertNewlineAtCursor).
            while (part && isSpan(part) && part.currentText == "") {
              // Leave empty nodes that are alone on a line alone in
              // Opera, since that browsers doesn't deal well with
              // having 2 BRs in a row.
              if (window.opera && surroundedByBRs(part)) {
                this.next();
                part = this.get();
              }
              else {
                var old = part;
                this.remove();
                part = this.get();
                // Adjust selection information, if any. See select.js for details.
                select.snapshotMove(old.firstChild, part && (part.firstChild || part), 0);
              }
            }
            
            return part;
          }
docs: Advance to the next part that is not empty, discarding empty parts.