imapsync help? (Was: Changing IMAP provider)

[toke lahti]

Title says what I'm (trying) to do.
Copying IMAP folders isn't easy, when they are big.
Current Thunderbird breaks down every time.

Just tried Apple Mail and the source folder has 5099 mails and the destination got 5096.
Don't understand why this smart folder setting does not find the 3 missing mails:

?
It shows all mails in source.
(Upper is the source, lower is the destination.)
Maybe Apple Mail looks UUID and it is changed when copying from one IMAP to another?

So, better ways:
How do you feel the security of these (a few identical pages are online):

Mailbox Imapsync Online

Would you insert your appleID password to some random webpage?

Has anybody experience on this:

GitHub - ridaamirini/ImapSyncClient: ImapSync Desktop Client

ImapSync Desktop Client. Contribute to ridaamirini/ImapSyncClient development by creating an account on GitHub.

github.com

 

[toke lahti]

Looks like ImapSyncClient misses the needed basic option: folders to be "synced" aren't defined in an y way.
So I guess it just syncs EVERYTHING?
Where do you put the synced folder's name?
Ah, and copy paste does not work. And syncs are not saved so you'd have to insert same things every time.
Total rubbish. Next.

 

[toke lahti]

Is there any IMAPSYNC users here?

What is the right expression to copy a folder from root to a subfolder?

Source is /folderX and destination is /folderY/folderX.
These does not seem to work:
imapsync --host1 test1.lamiral.info --user1 test1 --password1 secret1 —folder FOLDERX --host2 test2.lamiral.info --user2 test2 --password2 secret2 —-folder MBOX -—subfolder FOLDERX

or

imapsync --host1 test1.lamiral.info --user1 test1 --password1 secret1 —folder FOLDERX --host2 test2.lamiral.info --user2 test2 --password2 secret2 —-folder FOLDERX -—subfolder MBOX

What is the right expression?
Is there a simple use case examples somewhere?