How ERPNext download emails?

There is someone that could help me to understand how ERPNext/Frappe manage Inbox emails?
What I know is that emails are sync with IMAP (if I choose to use IMAP in domain configuration), but if I have a subfolder under my Inbox on the server, ERPNext it downloads also the emails from that subfolder or only from the parent Inbox?

And who can see the downloaded email?

T.I.A for your help