To make matters worse, I don't even know on which websites I have my YubiKey registered. I just checked mine, and it shows my Microsoft credentials and NVidia.

To make matters worse, I don't even know on which websites I have my YubiKey registered. I just checked mine, and it shows my Microsoft credentials and NVidia. But I know for a fact that I also use it on Vanguard and BofA (which doesn't support keys on iOS in case you're wondering). So I 1) cannot extract the masterkey from my YubiKey and move it to another one to make an exact duplicate 2) cannot discover the places where I registered my key For SSH you can have a 'sk' key and a normal one [0]. I went with the normal one and moved it into the YubiKey, at least that way I have a backup sitting SOMEWHERE. [0] https://cryptsus.com/blog/how-to-configure-openssh-with-yubikey-security-keys-u2f-otp-authentication-ed25519-sk-ecdsa-sk-on-ubuntu-18.04.html https://cryptsus.com/blog/how-to-configure-openssh-with-yubi... (not affiliated at all)