dovecot - Feb 2021 - Messages sent to alias+detail end up in INBOX

Hi, Anton!
> Hi Denis,
> 
> 
> > I expected that when I send a message to alias+detail at mydomain.tld,
> > it would go into the "detail" folder of user at
mydomain.tld. However,
> > it goes into the INBOX folder of user at mydomain.tld.
> > 
> > Is it the intended behavior?  
> 
> It is.
> 
> To achieve the desired folder, you need a sieve script:
> 
>
https://wiki.dovecot.org/Pigeonhole/Sieve/Examples#Plus_Addressed_mail_filtering
> 
> Ensure that you also subscribe to newly created mailboxes 
> (lda_mailbox_autosubscribe=yes).
Thanks for the advice.

I have tried using this code from the page you adised:

```
require ["variables", "fileinto", "envelope",
"subaddress", "mailbox"];

if envelope :matches :detail "to" "*" {
  # you can prefix with INBOX/ or INBOX. if necessary
  # remove :create if you want to permit only existing mailboxes
  fileinto :create "${1}";
}
```

I have also set

lda_mailbox_autosubscribe=yes

Also, I of course have recompiled the sieve with sievec. But the mail is still
dropped into INBOX. I suppose it's related to this piece of information also
found on that page:
> To work with Postfix, this requires that the envelope "to" still
> contains the full address, so pass it with the -a flag. 
If I understand this correctly, this is needed so that the messages sent to
alias+detail at mydomain.tld had "Delivered-To" header not with value
of "user at mydomain.tld" but with value of "user+detail at
mydomain.tld". Am I right?

So I have put into the postfix config this line:

mailbox_command = /usr/lib/dovecot/dovecot-lda -a "$RECIPIENT"

But in the headers of the received messages I have "Delivered-To: user at
mydomain.tld" instead of "Delivered-To: user+detail at
mydomain.tld". If this is the source of the problem, then how should I try
to fix it?

-- 
Respectfully,
Denis Shadrin

On Wed, 17 Feb 2021 18:13:13 +0300
<ml at shadrinden.ru> wrote:
> If I understand this correctly, this is needed so that the messages
> sent to alias+detail at mydomain.tld had "Delivered-To" header
not with
> value of "user at mydomain.tld" but with value of
> "user+detail at mydomain.tld". Am I right?
> 
> So I have put into the postfix config this line:
> 
> mailbox_command = /usr/lib/dovecot/dovecot-lda -a "$RECIPIENT"
> 
> But in the headers of the received messages I have "Delivered-To:
> user at mydomain.tld" instead of "Delivered-To:
> user+detail at mydomain.tld". If this is the source of the problem,
then
> how should I try to fix it?
> 
Sorry, I just forgot to comment out this line in the postfix config:
mailbox_transport?=?lmtp:unix:private/dovecot-lmtp

Now I commented it, and the messages properly have "Delivered-To:
user+detail at mydomain.tld" header. But they are still dropped into the
INBOX folder, so that was not the cause of the problem.

--
Respectfully,
Denis Shadrin