Recently, I just update my php to 8.1.6. I tried to upgrade roundcubemail to 1.5.3. It just will not let me connect with imap 993 port ssl. It shows unknown error. Without ssl, imap 143 works fine. I tried to enable openssl in php.ini. Should I point the ssl to the default one or the one used by hmailserver. Try both it does not work.