I've opted for the Mailman3 package installation on Ubuntu 22 LTS on top of a manually installed Mailman3 core package from the Ubuntu 20 Debian repository.

Everything is working great on my installation. However, if I try to enable hyperkitty in /etc/mailman.cfg postorius reports 500 status codes on all pages. /var/log/mailman3/mailman.log reports this error:

ModuleNotFoundError: No module named 'mailman3_hyperkitty'

Any idea why postorius can't seem to find the installed hyperkitty module?

Stack trace:

2023-02-08 12:48:14 [FALCON] [ERROR] GET /3.1/lists/test.listdev.ocdla.org/archivers => Traceback (most recent call last): File "falcon/app.py", line 361, in falcon.app.App.__call__ File "/usr/lib/python3/dist-packages/mailman/rest/lists.py", line 405, in on_get archiver_set = IListArchiverSet(self._mlist) File "/usr/lib/python3/dist-packages/zope/component/_api.py", line 156, in adapter_hook return sitemanager.queryAdapter(object, interface, name, default) File "/usr/lib/python3/dist-packages/zope/interface/registry.py", line 354, in queryAdapter return self.adapters.queryAdapter(object, interface, name, default) File "/usr/lib/python3/dist-packages/mailman/database/transaction.py", line 85, in wrapper return function(args[0], config.db.store, *args[1:], **kws) File "/usr/lib/python3/dist-packages/mailman/model/mailinglist.py", line 614, in __init__ for archiver in config.archivers: File "/usr/lib/python3/dist-packages/mailman/config/config.py", line 280, in archivers archiver = call_name(class_path) File "/usr/lib/python3/dist-packages/mailman/utilities/modules.py", line 69, in call_name named_callable = find_name(dotted_name) File "/usr/lib/python3/dist-packages/mailman/utilities/modules.py", line 52, in find_name module = import_module(module_path) File "/usr/lib/python3.10/importlib/__init__.py", line 126, in import_module return _bootstrap._gcd_import(name[level:], package, level) File "<frozen importlib._bootstrap>", line 1050, in _gcd_import File "<frozen importlib._bootstrap>", line 1027, in _find_and_load File "<frozen importlib._bootstrap>", line 1004, in _find_and_load_unlocked ModuleNotFoundError: No module named 'mailman3_hyperkitty'