anchor.diff:  
   ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
   
  -;;; BASIC-PANE
  +;;; BASIC PANE
   
   (defclass basic-pane (;; layout-protocol-mixin
                         standard-space-requirement-options-mixin
  
positive.code:                     (- width border-width border-width)
                      (- height border-width border-width)))))
  
  ;;; OUTLINED-PANE
  
  ;; same as SPACING-PANE but a different default background.
  
  
negative.code:   (note-input-focus-changed (sheet-child pane) state))
  
  ;;;;
  ;;;; SCROLLER PANE
  ;;;;
  
  ;;; How scrolling is done
  