Horde shared mailboxes - dovecot

Question

I'm trying to set up one mailbox to be shared with another one using steps described here but for some reason I do not see that option in my mailbox (logged as an admin) even I have set ACL as a true in the IMP configuration.
From dovecot -n:
auth_debug = yes
auth_debug_passwords = yes
auth_master_user_separator = *
auth_mechanisms = plain login
auth_verbose = yes
auth_verbose_passwords = yes
dict {
acl = mysql:/usr/etc/dovecot/dovecot-dict-sql.conf.ext
}
disable_plaintext_auth = no
lda_mailbox_autosubscribe = yes
log_path = /var/log/dovecot.log
mail_home = mdbox:/mnt/homedirs/%2Mu/%2.2Mu/%u
mail_location = mdbox:/mnt/mailboxes/%2Mu/%2.2Mu/%u
mail_plugins = acl
mail_shared_explicit_inbox = yes
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 vnd.dovecot.pipe vnd.dovecot.filter vnd.dovecot.execute
namespace {
list = children
location = mdbox:/mnt/mailboxes/%%2Mu/%%2.2Mu/%%u
prefix = shared/%%u/
separator = /
subscriptions = yes
type = shared
}
namespace inbox {
inbox = yes
location =
mailbox Drafts {
auto = subscribe
special_use = \Drafts
}
mailbox INBOX {
auto = subscribe
}
mailbox Junk {
special_use = \Junk
}
mailbox Sent {
auto = subscribe
special_use = \Sent
}
mailbox "Sent Messages" {
special_use = \Sent
}
mailbox Trash {
auto = subscribe
special_use = \Trash
}
prefix =
separator = /
subscriptions = yes
}
passdb {
args = /usr/etc/dovecot/mastership-sql.conf
driver = sql
master = yes
pass = yes
}
passdb {
args = /usr/etc/dovecot/dovecot-sql.conf.ext
driver = sql
}
plugin {
acl = vfile
acl_defaults_from_inbox = yes
acl_shared_dict = proxy::acl
sieve_execute_socket_dir = sieve-execute
sieve_extensions = +vnd.dovecot.execute +vnd.dovecot.filter +vnd.dovecot.pipe
sieve_filter_socket_dir = sieve-filter
sieve_pipe_socket_dir = sieve-pipe
sieve_plugins = sieve_extprograms
}
service dict {
unix_listener dict {
user = dovecot
}
}
service imap-postlogin {
executable = script-login /usr/etc/dovecot/imappostlogin
user = $default_internal_user
}
service imap {
executable = imap imap-postlogin
}
ssl = no
ssl_cert = </etc/pki/tls/certs/hostname.bundle
userdb {
args = uid=dovecot gid=dovecot home=/mnt/mailboxes/%%2Mu/%%2.2Mu/%%u
driver = static
}
protocol lmtp {
mail_plugins = acl sieve
}
protocol lda {
mail_plugins = acl sieve
}
protocol imap {
mail_plugins = acl imap_acl
}
Any tips on that?

Answer 1

It came up that for some reason backends.local.php shouldn't be a modified copy of backends.php. Simple - avoid default array notification for config but rather to set it as
<?php
$servers['imap']['disabled'] = true;
$servers['advanced']['disabled'] = false;
$servers['advanced']['secure'] = 'tls';
$servers['advanced']['debug'] = '/tmp/imp_imap.log';
$servers['advanced']['debug_raw'] = true;