Blazor Wasm AAD B2C authentication issue

Describe the bug

Hi, I am struggling with the below error. Can’t figure out the root cause. I have a Blazor Wasm application with AAD B2C authentication. Login works fine, but after some time I get the below error. Any ideas what could be the problem?

Based on the console logs, it seems that ID token is undefined.

ClientAuthError: null_or_empty_id_token: The idToken is null or empty. Please review the trace to determine the root cause. Raw ID Token Value: undefined

Further technical details

• Dotnet version: 5.0.100
• Project dependencies

` <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="5.0.1" />

<PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="5.0.1" PrivateAssets="all" />

<PackageReference Include="Microsoft.Authentication.WebAssembly.Msal" Version="5.0.1" />

<PackageReference Include="Microsoft.Extensions.Logging.Configuration" Version="5.0.0" />

<PackageReference Include="System.Net.Http.Json" Version="5.0.0" />

`

[juho-hanhimaki]

I did manually build a updated version of AuthenticationService.js which included patch https://github.com/dotnet/aspnetcore/pull/28498 AND updated the msal-browser library to 2.8.0 (https://github.com/dotnet/aspnetcore/issues/29010) (required some changes in the typescript source, but somehow got it working 😅).

Now the issue is gone for me. Don’t know which one of those two things fixed the issue, but the main thing for me is that the issue seems to be gone with those steps.

[ismailhozza]

Hi, I think this issue is resolved for me also. I did several changes, so I am not sure which one possibly fixed the issue. I updated the dependencies like @juho-hanhimaki and added couple of scopes (openid and offline_access) to the authentication config. So, I guess it can be closed for now.