Re: Dovecot upgrade from 2.3.x to 2.4.x: and mailbox_alias plugin

6 Nov 2025

      On 6. Nov 2025, at 9.04, Gerhard Wiesinger via dovecot <dovecot@dovecot.org> wrote:
...
On 2025-11-05 09:05, Timo Sirainen wrote:
...
On 2. Nov 2025, at 13.19, Gerhard Wiesinger via dovecot<dovecot@dovecot.org> wrote:
...
Hello,
Regarding dovecot upgrade from 2.3.x to 2.4.x and mailbox_alias plugin:
I've already converted my config and scripts but I'm still missing this config change:
plugin {
mailbox_alias_old = Spam
mailbox_alias_new = Junk
}
I saw in the linkhttps://doc.dovecot.org/2.4.0/installation/upgrade/2.3-to-2.4.html
mailbox-alias plugin    Depending on the use case, replacement may be the mailbox_special_use mailbox setting and/or Sieve filters.
Any ideas what's the best alternative?
Why do you need/want the mailbox_alias plugin? There is no direct replacement. But if you configure e.g.:
namespace inbox {
mailbox Junk {
special_use = \Junk
}
}
Then modern clients should use it. The worst part of mailbox_alias plugin was that it caused the mailbox content to be duplicated on client side for both old and new mailboxes.
Hello Timo,
I've already configured:
mailbox Spam {
auto = subscribe
special_use = \Junk
}
Is that additionally as an alias possible?
mailbox Junk {
auto = subscribe
special_use = \Junk
}
You shouldn't do this. It just creates confusion for clients, and they'll have two different folders. There is no aliasing support anymore like before.
...
I think it was for compatibility issues with some clients (don't remember the reason anymore) which have different Spam folders.
Maybe there's not even any need for tit anymore?
...
...
...
Another question, is the following correct:
mail_home = /home/vmail/%n
mail_location = maildir:~/Maildir
=>
mail_home = /home/vmail/%{user | username}
mail_driver = maildir
mail_path = ~/Maildir
This is the same as above.
...
mail_inbox_path = ~/Maildir
This isn't harmful, but it doesn't do anything.
...
(Especially mail_inbox_path, I don't have a ".INBOX" directory currently, I guess .INBOX is now default. How to deal with this?)
This I don't understand. It's not using .INBOX by default, and with or without mail_inbox_path it's not using .INBOX (I just tested to be sure). If you see .INBOX then I need to see the full doveconf output.
Is
mail_inbox_path = ~/Maildir/.INBOX
With this setting you'll get the ~/Maildir/.INBOX/{cur|new|tmp} directories for INBOX.
...
then new default for?
mail_inbox_path = ~/Maildir
With this setting you'll get the ~/Maildir/{cur|new|tmp} directories for INBOX. Same if you don't specify mail_inbox_path.
I don't understand why you would be getting .INBOX/ directory with this configuration. We didn't change any defaults related to this. That isn't supposed to happen. That's why I was asking for a full doveconf output.
On 6. Nov 2025, at 9.04, Gerhard Wiesinger via dovecot
<dovecot@dovecot.org> wrote:
 On 2025-11-05 09:05, Timo Sirainen wrote:

   On 2. Nov 2025, at 13.19, Gerhard Wiesinger via
   dovecot&lt;dovecot@dovecot.org> wrote:

     Hello,

     Regarding dovecot upgrade from 2.3.x to 2.4.x and mailbox_alias
     plugin:
     I've already converted my config and scripts but I'm still missing
     this config change:
     plugin {
       mailbox_alias_old = Spam
       mailbox_alias_new = Junk
     }

     I saw in the
     linkhttps://doc.dovecot.org/2.4.0/installation/upgrade/2.3-to-2.4.html
     mailbox-alias plugin    Depending on the use case, replacement may
     be the mailbox_special_use mailbox setting and/or Sieve filters.

     Any ideas what's the best alternative?

   Why do you need/want the mailbox_alias plugin? There is no direct
   replacement. But if you configure e.g.:

   namespace inbox {
     mailbox Junk {
       special_use = \Junk
     }
   }

   Then modern clients should use it. The worst part of mailbox_alias
   plugin was that it caused the mailbox content to be duplicated on
   client side for both old and new mailboxes.

 Hello Timo,

 I've already configured:

   mailbox Spam {
     auto = subscribe
     special_use = \Junk
   }

 Is that additionally as an alias possible?

   mailbox Junk {
     auto = subscribe
     special_use = \Junk
   }
You shouldn't do this. It just creates confusion for clients, and they'll
have two different folders. There is no aliasing support anymore like
before.
 I think it was for compatibility issues with some clients (don't
 remember the reason anymore) which have different Spam folders.
Maybe there's not even any need for tit anymore?
     Another question, is the following correct:
     mail_home = /home/vmail/%n
     mail_location = maildir:~/Maildir
     =>
     mail_home = /home/vmail/%{user | username}
     mail_driver = maildir
     mail_path = ~/Maildir

   This is the same as above.

     mail_inbox_path = ~/Maildir

   This isn't harmful, but it doesn't do anything.

     (Especially mail_inbox_path, I don't have a ".INBOX" directory
     currently, I guess .INBOX is now default. How to deal with this?)

   This I don't understand. It's not using .INBOX by default, and with or
   without mail_inbox_path it's not using .INBOX (I just tested to be
   sure). If you see .INBOX then I need to see the full doveconf output.

 Is

 mail_inbox_path = ~/Maildir/.INBOX
With this setting you'll get the ~/Maildir/.INBOX/{cur|new|tmp}
directories for INBOX.
 then new default for?

 mail_inbox_path = ~/Maildir
With this setting you'll get the ~/Maildir/{cur|new|tmp} directories for
INBOX. Same if you don't specify mail_inbox_path.
I don't understand why you would be getting .INBOX/ directory with this
configuration. We didn't change any defaults related to this. That isn't
supposed to happen. That's why I was asking for a full doveconf output.