Hi, I am new to Dovecot and Debian, but I seem to have got Dovecot up and running with local delivery and then switched to LMTP. I am running Debian 12.7 and Webmin 2.202 to try and get things running, but I've had to tweak files. Also Webmin did not install dovecot-lmtpd, dovecot-sieve or dovecot-managesieved, so I did that manually. I have tried following the configuration guide from Dovecot (but there seems to be little there) and other sources I've found on the internet, but there is nothing I have found to get sieve listening on port 4190 when checked with ss.

My Dovecot config from dovecot -n is:

# 2.3.19.1 (9b53102964): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.5.19 (4eae2f79)
# OS: Linux 6.1.0-26-amd64 x86_64 Debian 12.7
# Hostname: my.fqdn
auth_username_format = %Ln
disable_plaintext_auth = no
first_valid_uid = 1000
mail_location = maildir:~/Maildir
mail_privileged_group = mail
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext
namespace inbox {
  inbox = yes
  location =
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix =
}
passdb {
  driver = pam
}
plugin {
  sieve = file:~/sieve;active=~/.dovecot.sieve
}
protocols = imap lmtp
service lmtp {
  unix_listener /var/spool/postfix/private/dovecot-lmtp {
    group = postfix
    mode = 0600
    user = postfix
  }
}
service managesieve-login {
  inet_listener sieve {
    port = 4190
  }
}
ssl_cert = </etc/letsencrypt/live/mydomain.com/fullchain.pem
ssl_client_ca_dir = /etc/ssl/certs
ssl_dh = # hidden, use -P to show it
ssl_key = # hidden, use -P to show it
userdb {
  driver = passwd
}
protocol lmtp {
  mail_plugins = " sieve"
  postmaster_address = nick@mydomain.com
}
protocol lda {
  mail_plugins = " sieve"
}

Dovecot packages installed from the Debian repos are:

dovecot-core/stable,stable-security,now 1:2.3.19.1+dfsg1-2.1+deb12u1 amd64 [installed]
dovecot-imapd/stable,stable-security,now 1:2.3.19.1+dfsg1-2.1+deb12u1 amd64 [installed]
dovecot-lmtpd/stable,stable-security,now 1:2.3.19.1+dfsg1-2.1+deb12u1 amd64 [installed]
dovecot-managesieved/stable,stable-security,now 1:2.3.19.1+dfsg1-2.1+deb12u1 amd64 [installed]
dovecot-pop3d/stable,stable-security,now 1:2.3.19.1+dfsg1-2.1+deb12u1 amd64 [installed]
dovecot-sieve/stable,stable-security,now 1:2.3.19.1+dfsg1-2.1+deb12u1 amd64 [installed]

Ultimately I intend to run manage sieve from Roundcube which I have already got running, or I may try a Thunderbird addon.

Can anyone give me some pointers, please?