anchor.diff:                                    :collect `((,char :press :meta :control :shift) key-press)))
      :resize-callback 'resize-callback))
   
  -(defun maybe-update-cache-font (lem-pane)
  +(defun update-font-if-required (lem-pane)
     (unless (lem-pane-normal-font lem-pane)
       (change-font lem-pane (car *default-font-spec*) (cdr *default-font-spec*))))
   
  
positive.code:                      0 0))))
  
  (defun lem-pane-char-size (lem-pane)
    (maybe-update-cache-font lem-pane)
    (destructuring-bind (left top right bottom)
        (lem-pane-string-extent lem-pane)
      (values (- right left)
  
negative.code:      (gp:clear-graphics-port (lem-pane-pixmap lem-pane)))))
  
  (defun change-foreground (lem-pane color)
    (when-let (color (convert-color color nil))
      (setf (capi:simple-pane-foreground lem-pane) color)))
  
  (defun change-background (lem-pane color)
    (when-let (color (convert-color color nil))
      (setf (capi:simple-pane-background lem-pane) color)))
  