Traceback (most recent call last):
  File "/usr/share/software-center/softwarecenter/view/widgets/pathbar2.py", line 120, in append
    prev, did_shrink = self.__append(part, do_callback)
  File "/usr/share/software-center/softwarecenter/view/widgets/pathbar2.py", line 221, in __append
    self.set_active(part, do_callback)
  File "/usr/share/software-center/softwarecenter/view/widgets/pathbar2.py", line 90, in set_active
    prev, redraw = self.__set_active(part, do_callback)
  File "/usr/share/software-center/softwarecenter/view/widgets/pathbar2.py", line 202, in __set_active
    part.callback(self, part)
  File "/usr/share/software-center/softwarecenter/view/availablepane.py", line 382, in on_navigation_details
    self.nav_history.navigate(AppDetailsNavigationItem(self))
  File "/usr/share/software-center/softwarecenter/view/navhistory.py", line 44, in navigate
    logging.debug("submit navitem for history: %s" % dest_nav_item)
  File "/usr/share/software-center/softwarecenter/view/navhistory.py", line 172, in __str__
    details.append("  apps_category.name: %s" % self.apps_category.name)
AttributeError: 'NoneType' object has no attribute 'name'