Steps to reproduce:

1. Try https://www.zabbix.com/documentation/7.4/en/manual/introduction/whatsnew#tls-encryption-between-frontend-and-server

Result:

1. Trailing whitespace added to zabbix_server.conf on upgrade
2. No documentation whether TLSCAFile= applies also to TLSFrontendAccept=cert or how server validates frontend certificate in general. Not in config file and not in documentation:

   Parameter	Description
   TLS CA file	Specify the full path to the Certificate Authority (CA) certificate file used to verify the server’s certificate.

Also TLSFrontendCertSubject= allows only one string causing same PKI problems in frontend HA as TLSServerCertSubject in ZBX-24939 for server HA.