Loading thmes in cinnamon-settings doesn't bring up the themes dialog. Starting
in konsole shows the following Code:

Loading Themes module
Traceback (most recent call last):
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 670,
in button_press
    self.side_view_nav(widget, None, category)
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 174,
in side_view_nav
    self.go_to_sidepage(cat, filtered_path, user_action=True)
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 189,
in go_to_sidepage
    sidePage.build()
  File "/usr/share/cinnamon/cinnamon-settings/bin/SettingsWidgets.py", line
213, in build
    self.module.on_module_selected()
  File "/usr/share/cinnamon/cinnamon-settings/modules/cs_themes.py", line 120,
in on_module_selected
    widget.sync_initial_switch_state()
  File "/usr/share/cinnamon/cinnamon-settings/bin/CinnamonGtkSettings.py", line
321, in sync_initial_switch_state
    editor = get_css_editor(self.selector)
  File "/usr/share/cinnamon/cinnamon-settings/bin/CinnamonGtkSettings.py", line
80, in get_css_editor
    css_instance = GtkCssEditor(selector)
  File "/usr/share/cinnamon/cinnamon-settings/bin/CinnamonGtkSettings.py", line
105, in __init__
    for rs in stylesheet[0]:
TypeError: 'AtRule' object is not iterable