[icelancer]

Just tried this with my Yubikey Nano and Vanguard Investments, after changing my u2f to "true" in about:config. Does not work at all. Vanguard shows the Yubikey login prompt but it doesn't activate the Yubikey, and pushing the key just spits out a OTP and dumps it to the browser search bar. Oh well.

[richipargo]

I used to have this issue but in my case it just meant I was missing some OS dependencies so it might vary on a case by case