Changing IMAP separator - does it break things?

Filip Hajný
Wed, 14 Oct 2020 09:36:43 -0000

14. 10. 2020 v 11:28, Markus Winkler <ml at
irmawi.de>:
>
> Hi Victor,
>
> On 14.10.20 04:36, Victor Sudakov wrote:
>> Do you think I can change the hierarchy separator in the
"inbox"
>> namespace without breaking other clients and the mail layout on disk,
>> losing mail etc?
>
> I personally would try to avoid such a change (really IMHO), especially if
it's "only":
>
>> I don't want to break mail for 50 people just to please one Mac
Mail
>> user.
>
> _one_ user. Could Thunderbird or another IMAP client be an option for this
single user? And perhaps Apple can tell some details when their Mail client will
be standards-compliant?
>
> Besides that: changing the hierarchy separator is generally possible. But
you schould try and check that with a test system to prevent problems with your
productive environment and all the other users.
>

I had to do it with 10-20 live users and it went fine, nobody noticed anything
(I made the change in the night hours just to be sure though). I had to go down
and fix some erratic folder names that resulted from the botched separator
handling on some macOS Mail accounts.

The funny thing is that I set up a vanilla Dovecot server elsewhere and
subfolders worked fine there on the very same macOS client. Couldn?t find any
significant difference in the configs that would explain the problem, also the
relative lack of similar reports out there seemed mind boggling.

(I?m using the Dovecot-based Mailcow mail stack for production, which makes
troubleshooting a little more challenging.)

-F