anchor.diff:                                    0))
           (setf (screen-old-left-width screen)
                 (screen-left-width screen))
  +        (setf (screen-last-buffer-name screen)
  +              (buffer-name buffer))
  +        (setf (screen-last-buffer-modified-tick screen)
  +              (buffer-modified-tick buffer))
           (when (lem::window-use-modeline-p window)
             (screen-redraw-modeline window))
           (interface-redraw-view-after *implementation* (screen-view screen) focus-window-p)
  
positive.code: 
  (defun redraw-display-window (window force)
    (let ((focus-window-p (eq window (current-window)))
          (screen (lem::window-screen window)))
      (let ((scroll-n (when focus-window-p
                        (window-see window))))
        (when (or (not *native-scroll-support*)
                  (and scroll-n (>= scroll-n (screen-height screen))))
          (setf scroll-n nil))
        (when scroll-n
  
negative.code:   wrap-lines
    width
    modified-p
    last-buffer-name
    last-buffer-modified-tick
    (horizontal-scroll-start 0))
  
  (defun make-screen (x y width height use-modeline)
  