     super options, data
 
     @machine = new Machine machine: remote.revive data.machine
+    @workspaceListItemsById = {}
 
     @machine.isCollaborationMachine = data.machine.isCollaborationMachine
     @machine.isSharedMachine = data.machine.isSharedMachine

    @listWrapper = @listController.getView()

    @listController.getListView().on 'ItemWasAdded', (item) =>
      item.once 'WorkspaceDeleted', @bound 'handleWorkspaceDeleted'

    @addWorkspace ws  for ws in workspaces


    { workspaces } = @getData()

    delete @workspaceListItemsById[wsId]

    for ws, index in workspaces when ws.getId() is wsId
      return workspaces.splice index, 1

