I had the same problem with multiples mailboxes in IMAP (with folders and subfolders, many of them are > 500 messages, > 3000 messages (with filters)).
I had it on startup, without having the time to read one message.
I had the same problem with multiples mailboxes in IMAP (with folders and subfolders, many of them are > 500 messages, > 3000 messages (with filters)).
I had it on startup, without having the time to read one message.