imapsync is slower and doesn't support bidirectional sync. It however handles message identity better than mbsync (http://isync.sourceforge.net/) and supports using different authorization and authentication. For administering our mailserver, I first used imapsync and then patched mbsync to support the Auth header.
Thunderbird only supports moving from one mailbox to another, it doesn't support syncing whole namespaces. It also doesn't support syncing with namespace rewriting or syncing flags, timestamps or access rights. It does not allow using different authorization and authentication and is unsuitable for large syncs as you can't resume anything or have a progress bar. It is also pretty slow, because it does one mail at a time and is just not designed for this.
Note that I used the proper IMAP terms. A mailbox is what the layman probably calls a folder or directory, a namespace is what the laymen probably would call a mailbox or account.
> You wouldnt expect the post office to open your physical letters and write routing instructions to the postmen for delivery
Digital communication is based on the postmen reading, transcribing and copying your letters. There is a reason why digital communication is treated differently then letters by the law and why the legally mandated secrecy for letters doesn't apply to emails.
That's a software engineer that is limited to an mostly untyped macro language, with worse version control and poor tooling. It's not that software can't be written as an Excel spreadsheet, it is that it is just inefficient and failure prune.
reply