dovecot - Feb 2018 - mailbox_list_index documentation?

I find mailbox_list_index on some doc pages, but not explaination
to find what precisely it does? Would someone care to mind explain?
Thank you!


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On 11.02.2018 23:38, tai74 at vfemail.net wrote:
>
> I find mailbox_list_index on some doc pages, but not explaination
> to find what precisely it does? Would someone care to mind explain?
> Thank you!
>
>
> -------------------------------------------------
>
> ONLY AT VFEmail! - Use our Metadata Mitigator to keep your email out
> of the NSA's hands!
> $24.95 ONETIME Lifetime accounts with Privacy Features! 15GB disk! No
> bandwidth quotas!
> Commercial and Bulk Mail Options! 
mailbox_list_index enables list index, which keeps track of mailboxes
and reduces load by keeping certain mailbox related values in a separate
index file. Does not work together with mailbox_alias plugin yet.

Aki