Wow! I've just discovered that it's possible to use Secure Element as #u2f in GrapheneOS via hw-fido2-provider [1] (btw, thank you @S1m) in Vanadium even without any external token. Successfully added my Pixel smartphone as second factor device to my addy.io account. It works finally!
1. https://codeberg.org/s1m/hw-fido2-provider
#GrapheneOS #vanadium #vanadiumbrowser #fido2 #u2f #addyio #AnonAddy

