Ubiquity crashed with TypeError in partman_column_name (): argument of type 'NoneType' is not iterable

Traceback (most recent call last):
  File "/usr/lib/ubiquity/ubiquity/plugin.py", line 44, in wrapper
    return target(self, *args, **kwargs)
  File "/usr/lib/ubiquity/plugins/ubi-partman.py", line 625, in partman_column_mountpoint
    mountpoint = self.controller.dbfilter.get_current_mountpoint(partition)
  File "/usr/lib/ubiquity/plugins/ubi-partman.py", line 1593, in get_current_mountpoint
    if ('method' in partition and 'acting_filesystem' in partition and
TypeError: argument of type 'NoneType' is not iterable
Exception in GTK frontend (invoking crash handler):

and many others similar

The second attempt off this installation in manual partitioning selected from the option window went well till the end

Hello Jean-baptiste, I've suscribed you just to evaluate if this can be a dup of the bug 912563.
Sorry if disturb
Thanks
Fabio

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/918797