Title: ASWebAuthenticationSession fails when Chrome is open & Safari is closed → Scheme '(null)' is not valid as per RFC 3986

Environment

  • App: Flutter desktop (macOS primary; Windows/Linux also used)

  • SDK/Packages: auth0_flutter

  • Platforms: macOS, Windows/Linux unaffected

  • Browser state: Chrome open, Safari closed (Chrome default)

Summary

Login via auth0_flutter works in all other cases, but fails only when Chrome is freshly open and Safari is closed on macOS.

Errors observed

  1. First attempt (useHTTPS: true) throws:
WebAuthenticationException (OTHER: An unexpected error occurred.
CAUSE: Error Domain=com.apple.AuthenticationServices.WebAuthenticationSession Code=3
"Scheme '(null)' is not valid as per RFC 3986."
UserInfo={NSDebugDescription=Scheme '(null)' is not valid as per RFC 3986.})

  1. Fallback attempt (useHTTPS: false, custom scheme) immediately completes as canceled (SDK surfaces “User cancelled session.”) after Chrome’s “open this app?” prompt flashes.

Hi @lam1310

Welcome to the Auth0 Community!

Could you try adding in your .gradle file this following line or confirm if you already have:

manifestPlaceholders = [auth0Domain: "your_domain", auth0Scheme: "https"]

Otherwise, it is quite hard to troubleshoot the issue itself without taking a look at your code and understand exactly what is your configuration and where this error is being thrown.
I would highly recommend to open an issue on the SDKs Github page or you can try opening a support ticket since your account is under a free trial at this time for live support and troubleshooting.

If you have any other questions, let me know!

Kind Regards,
Nik