anchor.diff:  					      :structure-notify
   					      :pointer-motion)))
     (when (null (port-lookup-mirror port sheet))
  -    (let* ((desired-color (medium-background sheet))
  +    (let* ((desired-color +white+ #+NIL (medium-background sheet))
              (color (multiple-value-bind (r g b)
                         (color-rgb desired-color)
                       (xlib:make-color :red r :green g :blue b)))
  
positive.code: (defmethod initialize-clx ((port clx-port))
    (let ((options (cdr (port-server-path port))))
      (setf (clx-port-display port)
  	  (xlib:open-display (getf options :host "") :display (getf options :display-id 0)))
      (setf (xlib:display-error-handler (clx-port-display port))
  	  #'clx-error-handler)
      (setf (clx-port-screen port) (nth (getf options :screen-id 0)
  				      (xlib:display-roots (clx-port-display port))))
      (setf (clx-port-window port) (xlib:screen-root (clx-port-screen port)))
      (make-graft port)
      ))
  
  (defun realize-mirror-aux (port sheet
  
negative.code: 
  ;;; CLX-PORT class
  
  (defclass clx-port (basic-port)
    ((display :initform nil
  	    :accessor clx-port-display)
     (screen :initform nil
  