Fetchmail fails on folders with German umlauts

[NicolasGoeddel]

Environment & Version

• Docker Compose version v2.20.0
• MailU version 2.0

Description

When trying to fetch the folder Entwürfe from it results in an error. When you encode the name manually to Entw&APw-rfe according to the IMAP UTF-7 encoding scheme (see here) it works.

Replication Steps

• Add a fetchmail configuration, e.g. a web.de account
• Add the folder Entwürfe to be fetched
• Wait for the cronjob to execute

Observed behaviour

• fetchmail runs into an ERROR

Expected behaviour

• fetchmail should work just fine by encoding the folders to be fetched beforehand

Logs

mailu-fetchmail-1  | 2023-10-22T13:26:12.475249522Z fetchmail: mailbox selection failed
mailu-fetchmail-1  | 2023-10-22T13:26:12.481254947Z fetchmail: client/server synchronization error while fetching from <private>@web.de@imap.web.de
mailu-fetchmail-1  | 2023-10-22T13:26:12.491866138Z Sleeping for 600 seconds
mailu-fetchmail-1  | 2023-10-22T13:26:12.491939658Z fetchmail: Query status=7 (ERROR)

[ghostwheel42]

Thanks for pointing this out. Can you create a PR to fix this in fetchmail.py?

[ghostwheel42]

As pointed out in #2997 the folders input also needs to be updated to support spaces in folder names.
Maybe this can be done by using the select2 library already used in other locations.