Just pull mails from POP3S servers (TLS can be disabled) and put them in
local Maildirs. Proxies can be used, onion can be used.
RFC6856 compliant (UTF8 before RETR) so works with Courier as well.
It can keep messages on the server, but does not remember/store which ones were seen before.
Based on github.com/unkaktus/mm
Install
go install github.com/pepa65/m2m@latest
An example config file is .m2m.conf. If it is put in ~/ it is used as
the sole "Default" account to be used. Alternatively, ~/.m2m.conf can be
a directory with account config files (whose filename is taken to be the
'account name') which are all used when run in lexical order.
The config files have the POP3S server config details and the Maildir location:
username: POP3S username
password: POP3S password
tlsservername: Server domainname according to the certificate
serveraddress: IP/Domainname address of the server
proxyaddress: Address of the proxy server (default: empty, not used)
tls: true/false - Use TLS (default) or not
keep: true/false - Keep messages on the POP3S server or delete them (default)
maildirpath: Path to the Maildir directory (default: ~/Maildir)