I think it's be great if the Firefox (soon to be Mozilla) accounts supported password-less Fido keys, AKA Yubikeys.
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Some potentially related ideas here:
Support Yubikey with PIN in Firefox for Linux and Mac
Yubikey is not usable with WebAuth on Firefox for Android
Support WebAuthn Passkeys
Yeah there’s really no reason why Mozilla Accounts shouldn’t support FIDO2 & U2F Security Keys
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