Captive Portal WebView On-Submit of Username Error of {"error":"Invalid username"}

[ManiAnalist]

Domains that I have put in walled garden are:
.appspot.com,.unpkg.com,.googleapis.com

The host used to test is: https://passkeys-demo.appspot.com

Would be pivotal to bring passkey support to webview.... Thoh am not sure which repo to RFC for such feature support (: