No, I said I'm using a Yubico Security Key. This is not a Yubikey. This key has no storage. How can it possibly store resident keys? The YubiKey Manager app can't even connect to this key. It's very basic, it has no TOTP slots, it has no configuration, it only does FIDO2. How would resident keys get in there in the first place? The article cites a strict limit on the number of slots, but it has zero slots.
In Chrome 114.0.5735.199 on Windows 10 Pro, there is no "security key settings pane". The closest thing available is "Privacy and Security -> Security -> Manage phones (control which phones you use as security keys.)"
However, in terms of resident credentials, I thank the GP and I stand corrected, because Yubico's own specs say that this key sports 25 slots. I wonder how many are currently in use, and which version of the CTAP protocol it is using...
Additionally, U2F/CTAP1 does not support resident keys anyway (IIRC).
I'd check your firmware versions, update your Authenticator, ensure you have a PIN set and ensure you're correctly saving a resident key on your device when registering with a service.
For Chrome, a visit to chrome://settings/securityKeys[1] should do it, but I just tried it in a Windows VM and it is not present in the menu, while it is present on Linux and macOS.
[1] https://chromium.googlesource.com/chromium/src/+/HEAD/device...
I don't know about Microsoft specifically, but it's possible to register the same FIDO2-capable security key with a service as both a passkey and a U2F token.
You don’t have to do it this way. I configured my Yubikeys to be the second factor and not to use resident keys. It’s possible, although I don’t know if Microsoft allows users to roll back from “passwordless” and discoverable keys.
I want to state it explicitly: FIDO as technology allows either. It’s particular platform choice to go with discoverable keys.