Is it possible to find a sender's Public PGP (GPG) key from an encoded message?

Question

Could you find the sender's Public PGP (GPG) key from an encoded message?

Answer 1

Encrypted messages only contain the recipients' key IDs (and even that can be disabled).

You can only find the sender's key ID if the message was also signed – but the signature is encrypted too, so you're out of luck.

Either way, you would only find the key ID, not the key itself.