Traceback (most recent call last):
  File "/usr/lib/ubiquity/ubiquity/frontend/gtk_ui.py", line 1251, in on_next_clicked
    if ui.plugin_on_next_clicked():
  File "/usr/lib/ubiquity/plugins/ubi-partman.py", line 219, in plugin_on_next_clicked
    biggest_free = 'biggest_free' in self.extra_options
AttributeError: 'PageGtk' object has no attribute 'extra_options'