Claus-Justus Heine via Mailman-users writes:
Mmmh. So is this "won't fix"? No one?
Encoding issues are very difficult to diagnose from "it's wrong" without access to the actual server. However, Mailman 3 is designed to take advantage of Python's "universally encoded text" string representation (it happens to be wide-char Unicode, but that's not important to this issue). This means that we have to explicitly specify encoding when displaying text. On a monolingual site, if only one text is incorrectly encoded in the UI, almost always the template is the problem. Bugs in Mailman are of course always possible, but the current design dramatically improves the situation vs. Mailman 2.
The encoding of the welcome-message is wrong, regardless of the localization settings.
Are you using the default welcome message, or is it a custom message you added yourself? Either way, check that the template file in templates/de/list:user:notice:welcome.txt is encoded in UTF-8 (2 bytes per non-ASCII character), not in a Latin-1-ish encoding (1 byte per non-ASCII character) as was often the case for German in software until fairly recently.
Note that if you have a list-specific template, this will be stored in the RDBMS, not as a template in the file system.
As everything else works I assume that this is a bug in mailman v3.
Assume what you like, but it's probably easier and *much* quicker to fix if it's a user error. ;-) Another possibility, if you configured the template through the web, is an encoding error by the browser.
Is there any other work-around?
I think it's most likely that your welcome.txt template somehow is in a Latin-1 variant encoding rather than UTF-8. Figure out which encoding and reencode to UTF-8 using iconv or similar. If it's not that, I don't have any good ideas because you say other stuff is working. There's no reason why it would fail only for that template.
Are you sure other templates are working correctly?
Steve