==== Required information ====
- iRedMail version (check /etc/iredmail-release): 0.9.5-1
- Linux/BSD distribution name and version: Debian 8
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Apache
- Manage mail accounts with iRedAdmin-Pro? No
- Related log if you're reporting an issue:
====
Hi Zang,

Making sending e-mail tests for gondim+test@domain.net I realized that dovecot is creating mailboxes "test" instead of putting these emails to INBOX.
When I open my thunderbird not get the message because it was stored on the server in a mailbox called "test".

I could suffer an attack with sending several emails so:

gondim+adfdfsafg@domain.net
gondim+gafsgaftf@domain.net
gondim+qeqeeqeqeqe@domain.net

This would create several directories on my email server and I only see when using roundcube.

I would suggest the following default configuration /etc/dovecot/dovecot.conf:

protocol lda {
.
.
    lda_mailbox_autocreate = no
.
.
}

protocol lmtp {
.
.
    lmtp_save_to_detail_mailbox = no
    recipient_delimiter = +
}