Webauthenticator on android still has incorrect behaviour described in #22296

[phdonnelly]

Description

We are experiencing the same/similar issue described in #22296 where only on android builds of our app, when using WebAuthenticator to complete a successful authentication flow that redirects to a custom URL scheme like myapp://callback, the chrome window used for authentication will send a second, spurious call to to the authentication endpoint immediately after redirecting back to our app.

In our case this additional call silently fails as the first, successful auth request clears some intermediate cookies used during authentication when it completes. This does not directly affect the our app, however we have had to add additional code to our authentication endpoint to suppress the errors generated by the extra HTTP calls.

Steps to Reproduce

Create new MAUI application containing an authentication flow as described in WebAuthenticator as defined in https://learn.microsoft.com/en-us/dotnet/maui/platform-integration/communication/authentication?view=net-maui-9.0&tabs=android that connects to a mobile auth controller that uses a custom callback scheme to return control to the app via redirect.

Expected result; after successful authentication the browser window redirects back to the app via custom URL scheme and the browser cleanly exits

Actual result; on android specifically, after successful authentication the browser window does redirect back to the app via custom URL scheme, however the browser will then re-send another authentication attempt.

Link to public reproduction project repository

No response

Version with bug

9.0.0 GA

Is this a regression from previous behavior?

Not sure, did not test other versions

Last version that worked well

No response

Affected platforms

Android

Affected platform versions

Android 13

Did you find any workaround?

The issue can be worked around by catching the extra HTTP requests and discarding them.

Relevant log output

[Zhanglirong-Winnie]

Could you provide us with a sample project so we can investigate it further?
Looking forward to your reply!

[phdonnelly]

Sure let me work on creating a minimal copy of the app plus endpoint that displays this behaviour.