U2F: What URL is used as AppID?


Not an OAuth question, but a related one.

I am maintaining a list of (Web)Apps that use FIDO/U2F or FIDO2/WebAuthn. I’d need to know which URL is used as AppID. I know it’s SHA256 hash is f4e46bbf243a8c6854a4c836861468389cf229702682eca7e3faec89518c6559, but it is not https://twitter.com.

Any Twitter developer (ideally the one who worked on the current U2F implementation) here?