Closed issue by Justinizer on void-packages repository

https://github.com/void-linux/void-packages/issues/29739

Description:
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### System

* xuname:  
  * Void 5.11.9_1 x86_64 GenuineIntel uptodate rrrmFFFFFF
* package:  
  * kmail-20.12.3_1

### Expected behavior
* Should receive e-mail over StartTLS
### Actual behavior
* Throws error: `SASL(-4): no mechanism available: No worthy mechs found`
### Steps to reproduce the behavior
* Use Kmail and connect to an E-mail Server over StartTLS (Port: 143) with plain mechanism per IMAP. The server is using ECC certificates based on letsencrypt.
* I checked kmail with another system (ArchLinux and Debian) and used thunderbird on VoidLinux to exclude errors based on server. On ArchLinux and Debian KMail works.
(Personally I think that the SASL Plugin for PLAIN is missing)