anchor.diff:  
   (defmethod port-set-sheet-transformation ((port clx-port) (sheet mirrored-sheet-mixin) transformation)
     (declare (ignore transformation)) ;; why?
  +  (break)                               ;obsolete now
     (let ((mirror (sheet-direct-mirror sheet)))
       (multiple-value-bind (tr rg) (invent-sheet-mirror-transformation-and-region sheet)
         (multiple-value-bind (x y) (transform-position tr 0 0)
  
positive.code: 					     ;:pointer-motion
                                                :button-motion)))
    (when (null (port-lookup-mirror port sheet))
      (let* ((desired-color (typecase sheet
                              (sheet-with-medium-mixin
                                (medium-background sheet))
  
negative.code: ;; Top-level-sheet
  
  ;; this is evil.
  (defmethod allocate-space :after ((pane top-level-sheet-pane) width height)
    (when (sheet-direct-mirror pane)
      (with-slots (space-requirement) pane
        '(setf (xlib:wm-normal-hints (sheet-direct-mirror pane))
              (xlib:make-wm-size-hints 
               :width (round width)
               :height (round height)
               :max-width (min 65535 (round (space-requirement-max-width space-requirement)))
               :max-height (min 65535 (round (space-requirement-max-height space-requirement)))
               :min-width (round (space-requirement-min-width space-requirement))
               :min-height (round (space-requirement-min-height space-requirement)))))))
  
  
  