This is cool! Though if you need to use it, it's a possible sign that your institution hasn't enabled Security Key support. Duo is able to support FIDO-compat

This is cool! Though if you need to use it, it's a possible sign that your institution hasn't enabled Security Key support. Duo is able to support FIDO-compatible security keys, but it is something that has to be enabled by the institution's Duo admin (typically someone in an IT Security office). Once that's enabled, you can use something like a Yubikey, a Feitan key, or another FIDO-compatible key. If you're using Duo in a situation where FIDO doesn't work (like SSH), and you have to use push or a code, it's possible to enroll a Yubikey in Duo with the Yubico OTP method. That's more labor-intensive, as it requires configuring one of the Yubikey's authentication slots, but it works everywhere. That being said, I'm gonna let coworkers know about this!