OK. Here is what I see in mailman-web.log when attempting a download:
[pid: 2244|app: 0|req: 1/1] 59.167.198.231 () {48 vars in 981 bytes} [Fri Sep 6 11:11:45 2019] GET /archives/list/exp@jackrail.org/2019/9/ => generated 63387 bytes in 791 msecs (HTTP/1.1 200) 6 headers in 332 bytes (1 switches on core 0) [pid: 2244|app: 0|req: 2/2] 59.167.198.231 () {48 vars in 1013 bytes} [Fri Sep 6 11:11:47 2019] GET /archives/list/exp@jackrail.org/thread/EFHHXQIOW54KKB2LDN67JRHRUABZ5WDF/ => generated 23870 bytes in 873 msecs (HTTP/1.1 200) 6 headers in 332 bytes (1 switches on core 0) [pid: 2244|app: 0|req: 3/3] 59.167.198.231 () {48 vars in 1112 bytes} [Fri Sep 6 11:11:49 2019] GET /archives/list/exp@jackrail.org/thread/EFHHXQIOW54KKB2LDN67JRHRUABZ5WDF/replies?sort=thread&last_view=1567767799 => generated 4872 bytes in 75 msecs (HTTP/1.1 200) 6 headers in 329 bytes (2 switches on core 0) Traceback (most recent call last): File "/opt/mailman/mm/venv/lib/python3.7/site-packages/HyperKitty-1.3.0-py3.7.egg/hyperkitty/views/mlist.py", line 327, in stream_mbox msg = email.as_message() File "/opt/mailman/mm/venv/lib/python3.7/site-packages/HyperKitty-1.3.0-py3.7.egg/hyperkitty/models/email.py", line 188, in as_message subtype=mimetype[1], filename=attachment.name) File "/usr/lib/python3.7/email/message.py", line 1147, in add_attachment self._add_multipart('mixed', *args, _disp='attachment', **kw) File "/usr/lib/python3.7/email/message.py", line 1135, in _add_multipart part.set_content(*args, **kw) File "/usr/lib/python3.7/email/message.py", line 1162, in set_content super().set_content(*args, **kw) File "/usr/lib/python3.7/email/message.py", line 1092, in set_content content_manager.set_content(self, *args, **kw) File "/usr/lib/python3.7/email/contentmanager.py", line 35, in set_content handler = self._find_set_handler(msg, obj) File "/usr/lib/python3.7/email/contentmanager.py", line 58, in _find_set_handler raise KeyError(full_path_for_error) KeyError: 'builtins.NoneType' [pid: 2244|app: 0|req: 4/4] 59.167.198.231 () {48 vars in 1173 bytes} [Fri Sep 6 11:11:50 2019] GET /archives/list/exp@jackrail.org/export/exp@jackrail.org-EFHHXQIOW54KKB2LDN67JRHRUABZ5WDF.mbox.gz?thread=EFHHXQIOW54KKB2LDN67JRHRUABZ5WDF => generated 0 bytes in 40 msecs (HTTP/1.1 200) 5 headers in 236 bytes (0 switches on core 0)
Andrew