При работе с теми же «настройками». Я получаю эту вещь: -

cinnamon-settings display
Traceback (most recent call last):
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 734, in <module>
    window = MainWindow()
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 313, in __init__
    for module in modules:
  File "/usr/share/cinnamon/cinnamon-settings/modules/cs_calendar.py", line 6, in <module>
    import pytz
ModuleNotFoundError: No module named 'pytz'
Error in sys.excepthook:
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/apport_python_hook.py", line 153, in apport_excepthook
    with os.fdopen(os.open(pr_filename,
FileNotFoundError: [Errno 2] Нет такого файла или каталога: '/var/crash/_usr_share_cinnamon_cinnamon-settings_cinnamon-settings.py.1000.crash'
 
Original exception was:
Traceback (most recent call last):
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 734, in <module>
    window = MainWindow()
  File "/usr/share/cinnamon/cinnamon-settings/cinnamon-settings.py", line 313, in __init__
    for module in modules:
  File "/usr/share/cinnamon/cinnamon-settings/modules/cs_calendar.py", line 6, in <module>
    import pytz
ModuleNotFoundError: No module named 'pytz'

Следуя предложениям на форуме о переустановке пакетов `python3-pil` и `python-pil`, я переустановил пакеты `python3-tz` и `python-tz`

sudo apt install --reinstall python3-tz python3-tz