As of Gpg4win 4.0.2 and GnuPG 2.3.6, everything worked fine. After an update to Gpg4win 4.0.3 and GnuPG 2.3.7:
- When opening Kleopatra, the OpenPGP tab for smartcards doesn't show up.
- running gpg --card-edit --expert doesn't show the "regular" for YubiKeys for all fields and instead the following fields are changed
Version ..........: 1.0
Manufacturer .....: ?
Max. PIN lengths .: 3 -2 0
PIN retry counter : 0 0 0
Key Attributes are missing
Resetting the card goes back to normal with all card info showing correctly, with the key attributes being rsa2048. After trying to change the key attributes and choosing ECC (any of them), is says "Card Error". Exiting and removing and reinserting the card and then running gpg --card-edit --expert again, shows the incorrect text in 2).
Downgrading version fixes the problem. As of the current version, ECC keys are unuseable on OpenPGP Cards. I have not checked for locally-stored keys or for keys on the PIV applet.