anchor.diff:              let world = subscribeToEntityEvents form world
               refreshEntityTreeView form world
               refreshEntityPropertyGrid form world
  -            selectLayer form selectedLayer world
  +            selectLayer selectedLayer form world
               world
   
       let private handleTraceEventsCheckBoxChanged (form : GaiaForm) (_ : EventArgs) =
  
positive.code:     let private handleNuMouseRightDown (form : GaiaForm) (_ : Event<MouseButtonData, Game>) world =
          let handled = if World.isTicking world then Cascade else Resolve
          let mousePosition = World.getMousePositionF world
          let (_, world) = tryMousePick form mousePosition world
          let world = World.updateUserValue (fun editorState -> { editorState with RightClickPosition = mousePosition }) world
          (handled, world)
  
  
negative.code:                     else node.Collapse ())
              treeState
  
      let private addEntityTreeViewNode (entity : Entity) (form : GaiaForm) world =
          let entityGroupName = getTypeName (entity.GetDispatcher world)
          let treeGroup = form.entityTreeView.Nodes.[entityGroupName]
          let treeGroupNodeName = scstring entity.EntityAddress
  