>You haven't used it with imap and lots of mail then. I get 100…500 emails daily and tb freezes for 15…60 seconds at a time. My inbox is kept in order by a bunch of filters, but the thing still freezes if I have lots of e-mails in another mailbox.

I do, around 100k mails in various dirs with order of magnitude higher volume than you. Just need to set it up

> The mailboxes are very inefficient, being regular mboxes with an index. I'd rather have the e-mails in a sqlite database. A Maildir on disk is a waste of inodes and a liability when one does a search or archives the thing. Old mail is rarely touched and sqlite has a full text search function.

You can set it to maildir style, sadly impossible after account creation and requires unbelievably much effort for such simple change.

Like, this piece of shit asked me to restart client to change IMAP server name, who wrote that garbage?