I finally got around to testing this setup. First I verified that the template in /var/templates/site/no was picked up when subscribing. Then I changed the text, and it stopped working. If I add one of these three Norwegian letters to list:user:action:subscribe.txt, I get the following in logs/mailman.log:
UnicodeEncodeError: 'ascii' codec can't encode character '\xe5' in position 153: ordinal not in range(128)
Oct 04 19:18:41 2017 (29) Uncaught runner exception: 'ascii' codec can't encode character '\xe5' in position 153: ordinal not in range(128)
Oct 04 19:18:41 2017 (29) Traceback (most recent call last):
File "/usr/local/lib/python3.6/site-packages/mailman/core/runner.py", line 171, in _one_iteration
self._process_one_file(msg, msgdata)
File "/usr/local/lib/python3.6/site-packages/mailman/core/runner.py", line 264, in _process_one_file
keepqueued = self._dispose(mlist, msg, msgdata)
File "/usr/local/lib/python3.6/site-packages/mailman/runners/command.py", line 196, in _dispose
mlist, msg, msgdata, parts, results)
File "/usr/local/lib/python3.6/site-packages/mailman/commands/eml_membership.py", line 104, in process
ISubscriptionManager(mlist).register(subscriber)
File "/usr/local/lib/python3.6/site-packages/mailman/app/subscriptions.py", line 520, in register
list(workflow)
File "/usr/local/lib/python3.6/site-packages/mailman/app/workflow.py", line 69, in __next__
return step()
File "/usr/local/lib/python3.6/site-packages/mailman/app/subscriptions.py", line 336, in _step_send_confirmation
self.mlist, self.token, self.address.email))
File "/usr/local/lib/python3.6/site-packages/zope/event/__init__.py", line 32, in notify
subscriber(event)
File "/usr/local/lib/python3.6/site-packages/mailman/app/subscriptions.py", line 584, in handle_SubscriptionConfirmationNeededEvent
_handle_confirmation_needed_events(event, 'list:user:action:subscribe')
File "/usr/local/lib/python3.6/site-packages/mailman/app/subscriptions.py", line 576, in _handle_confirmation_needed_events
msg = UserNotification(email_address, confirm_address, subject, text)
File "/usr/local/lib/python3.6/site-packages/mailman/email/message.py", line 124, in __init__
@public
UnicodeEncodeError: 'ascii' codec can't encode character '\xe5' in position 153: ordinal not in range(128)
Oct 04 19:18:41 2017 (29) SHUNTING: 1507144721.896973+35dc93aa969a0934bf717ca07965b09924eca59d
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