Comment by abraxas

My OS (Arch), my browser (Firefox) and my hardware (Yubikey) all work fine with some sites. For example my Google account credentials are on my Yubikey passkey. But half of the sites that claim to support passkeys won't offer me the option to save the passkey on my hardware. Paypal is one such example. Facebook is another. I don't understand why. They seemingly only want to cooperate with cloud based passkey storage. I don't know what mechanics govern this.