pytyle crashed

[GoogleCodeExporter]

I just opened a mail attachment with gnumeric and noticed that pytyle2 stopped 
working with xfwm4. The error message on the console is:

Traceback (most recent call last):
  File "/usr/local/bin/pytyle2", line 59, in <module>
    d = Dispatcher(event_data)
  File "/usr/local/lib/python2.7/dist-packages/pt/dispatcher.py", line 20, in __init__
    getattr(self, self._event_data['event'])()
  File "/usr/local/lib/python2.7/dist-packages/pt/dispatcher.py", line 89, in PropertyNotifyEvent
    state.update_property(a)
  File "/usr/local/lib/python2.7/dist-packages/pt/state.py", line 155, in update_property
    m()
  File "/usr/local/lib/python2.7/dist-packages/pt/state.py", line 185, in update_NET_CLIENT_LIST
    Window.add(wid)
  File "/usr/local/lib/python2.7/dist-packages/pt/window.py", line 14, in add
    if Window.manageable(wid):
  File "/usr/local/lib/python2.7/dist-packages/pt/window.py", line 49, in manageable
    win_types = win.get_types()
  File "/usr/local/lib/python2.7/dist-packages/pt/ptxcb/window.py", line 238, in get_types
    return set([Atom.get_atom_name(anum) for anum in self._get_property('_NET_WM_WINDOW_TYPE')])
TypeError: 'NoneType' object is not iterable

I use today's build.

Original issue reported on code.google.com by hol...@informatik.htw-dresden.de on 9 Oct 2012 at 12:12