anchor.diff:                                        :test (list-pane-test pane))))))
               (fun item-values (gadget-value pane))))))
   
  -(defun generic-list-pane-item-from-event (pane event)
  +(defun generic-list-pane-item-from-x-y (pane mx my)
     "Given a pointer event, determine what item in the pane it has fallen upon. 
   Returns two values, the item itself, and the index within the item list."
  +  (declare (ignore mx))
     (with-bounding-rectangle* (sx0 sy0 sx1 sy1)  (sheet-region pane)
  -    (declare (ignorable sx0 sx1 sy1))                            
  -    (multiple-value-bind (mx my) (values (pointer-event-x event) (pointer-event-y event))
  -      (declare (ignore mx))
  +    (declare (ignorable sx0 sx1 sy1))
         (with-slots (items) pane
           (let* ((item-height (generic-list-pane-item-height pane))
                  (number-of-items (generic-list-pane-items-length pane))
  
positive.code: 
  (define-abstract-pane-mapping 'list-pane 'generic-list-pane)
  
  (defclass meta-list-pane (list-pane)
    ((mode        :initarg :mode
                  :initform :some-of
                  :reader list-pane-mode
  
negative.code: ;;; Common colors:
  
  (defmethod gadget-highlight-background ((gadget basic-gadget))
    (compose-over (compose-in #|+paleturquoise+|# +white+ (make-opacity .5))
                  (pane-background gadget)))
  
  (defmethod effective-gadget-foreground ((gadget basic-gadget))
  