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There's this thing: https://trykno.com/

As they're incredibly opaque about what they're doing, it's hard to tell whether they're part of the "get it wrong" crowd, but being incredibly opaque about what they're doing doesn't bode well.

I used this when I was doing web apps for small enterprises in early 2000's - I sent a random string in a hidden input in the login form and had some javascript concatenate the password and the random string and send me back the username, the random string and the hash of the concatenated string. I hope I got that right (not doing web apps any more since a long time ...).

You would want to use a token and the string and only accept the token to look up the string that you would only accept once and for a limited time.

Otherwise its vulnerable to replay attacks

Yes I think I was cashing the generated string server side for a while and checking if the string I received back had a matching entry in the cache, otherwise reject it.

Anyway, it's been a long time ago, and if I had to do it again today, i would rather not roll my own.

Fido (and now w3c)'s WebAuthn come to mind

Chip-and-pin credit cards use it. 2FA/Fido/Yubikey use it.

Amazon use it in their Cognito offering.