Traceback (most recent call last):
  File "/usr/sbin/computer-janitor-gtk", line 30, in <module>
    app.run(computerjanitorapp.GtkUserInterface)
  File "/usr/share/computerjanitor/computerjanitorapp/app.py", line 101, in run
    ui.run(options, args)
  File "/usr/share/computerjanitor/computerjanitorapp/ui_gtk.py", line 211, in run
    self.create_column('unused_treeview', self.unused_filter)
  File "/usr/share/computerjanitor/computerjanitorapp/ui_gtk.py", line 291, in create_column
    treeview = self.widgets[widget_name]
KeyError: 'unused_treeview'