boxy-mode-cycle-visibility: How to set to show "MORE CONTENTS"?

(defun boxy-mode-cycle-visibility ()
  "Cycle visibility on all children in the current buffer."
  (interactive)
  (setq boxy--visibility (mod (+ 1 boxy--visibility)
                              (+ 1 boxy--max-visibility)))
  (if (= 0 boxy--visibility)
      (setq boxy--visibility 1))
  (cond
   ((= 1 boxy--visibility) (message "OVERVIEW"))
   ((= 2 boxy--visibility) (message "CONTENTS"))
   ((= 3 boxy--visibility) (message "MORE CONTENTS")))
  (boxy-mode-update-visibility)
  (boxy-mode-redraw))

How to set to show "MORE CONTENTS"?