[rfoo]

This passcode is inherently limited to the service it bound to (IMAP or POP3), that's the whole point: don't expose your account password to something which only needs a finer-grained access.

Edit: that's incorrect, see replies.

[bandrami]

"This App Password provides full access to your Google account"

-- Google, when you make an App Password

[rfoo]

Ah, ok, I just tried and I'm wrong. That's correct, it provides full access.

[fps_doug]

You're directly contradicting your sibling comment. I guess I'll experiment with this in the coming days, although I'm a little worried tinkering too much will just completely lock me out of my account.