PGP Authentication with gpg4win+ssh

[NIIBE Yutaka]

Chris Horry <zerbey at gmail.com> wrote:
> I also created an Authentication subkey for my other PGP Key, the only
> difference being it's not on my Yubkiey but in my regular keyring with
> Kleopatra.  This same key works just fine on my Linux boxes when I use it
> for authentication between them but not in Windows.  PuTTY shows no keys
> available in the agent and thus my login is rejected.
>
> Is there some setting I'm missing or does gpg4win only support PGP
> authentication with SSH via a smart card?

Your authentication subkey should be listed in .gnupg/sshcontrol, while
it is automatically supported for Gnuk Token and OpenPGP card.

For detail, I found this post:
https://ryanlue.com/posts/2017-06-29-gpg-for-ssh-auth#adding-keys
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