[MM3-users] Import Mailman 2.1.15 => Mailman 3 fails

Hi,

we want to replace our Mailman 2.1.15 installation and have installed Mailman 3 with Docker (maxking/docker-mailman).

Everything seems to be fine so far, but the import of the old mailing lists fails. There are two different exceptions:

MySQLdb._exceptions.OperationalError: (1366, "Incorrect string value: '\\xE2\\\x80\x8D0\xE2\\x80...' for column mailmandb.hyperkitty_email.content at row 1")

as well as

MySQLdb._exceptions.OperationalError: (1048, "Column 'description' cannot be null")

The complete log can be found here: https://www.dropbox.com/s/htd4eia1cg1kyi7/mailman3_import_log.txt?dl=0

Any idea what's going wrong here?

Kind regards, Jens