it seems clear that prf is now preferred, although I'm not sure if it could be used compatibly with our existing vaults c.f. https://github.com/Yubico/python-fido2/commit/56475d616f988b4b10fb07e15d5256e1225b01a5 https://www.w3.org/TR/webauthn-3/#prf-extension #2
it seems clear that prf is now preferred, although I'm not sure if it could be used compatibly with our existing vaults
c.f.
Yubico/python-fido2@56475d6
https://www.w3.org/TR/webauthn-3/#prf-extension
#2