anchor.diff:                       (1+ charpos)))))
   
   (defun disp-reset-lines (window)
  -  (let ((screen (lem::window-screen window))
  +  (let ((screen (window-screen window))
           (buffer (window-buffer window))
  -        (view-point (lem::window-view-point window)))
  +        (view-point (window-view-point window)))
       (with-point ((point view-point))
         (loop :for i :from 0 :below (screen-height screen)
               :do (let* ((line (lem-base::point-line point))
  
positive.code:             (if (plusp scroll-n)
                  (values (- (screen-height screen) scroll-n) (screen-height screen))
                  (values 0 (- scroll-n))))
          (lem::run-show-buffer-hooks window)
          (disp-reset-lines window)
          (adjust-horizontal-scroll window)
          (screen-display-lines screen
  
negative.code: (defmethod interface-redraw-window (implementation window force)
    (let ((focus-window-p (eq window (current-window)))
          (buffer (window-buffer window))
          (screen (window-screen window)))
      (let ((scroll-n (when focus-window-p
                        (window-see window))))
        (when (or (not (native-scroll-support *implementation*))
  