I found them in ExternalLoginInfo.Principal.Claims
Thanks. I hade made two mistakes:
https://community.abp.io/posts/how-to-customize-the-login-page-of-an-abp-blazor-application-by4o9yms
https://docs.abp.io/en/abp/latest/UI/AspNetCore/Customization-User-Interface#overriding-a-page-model-c
Now it's working 👍
My next question is how can I (in CreateExternalUserAsync()) access the claims I received via OpenIdConnect? My config looks like this:
private void ConfigureExternalProviders(ServiceConfigurationContext context, IConfiguration configuration)
{
context.Services.AddAuthentication()
.AddOpenIdConnect("AzureOpenId", "Azure AD OpenId", options =>
{
options.Authority = "https://login.microsoftonline.com/" + configuration["AzureAd:TenantId"] + "/v2.0/";
options.ClientId = configuration["AzureAd:ClientId"];
options.ResponseType = OpenIdConnectResponseType.CodeIdToken;
options.CallbackPath = configuration["AzureAd:CallbackPath"];
options.ClientSecret = configuration["AzureAd:ClientSecret"];
options.RequireHttpsMetadata = false;
options.SaveTokens = true;
options.GetClaimsFromUserInfoEndpoint = true;
options.Scope.Add("email");
options.Scope.Add("profile");
options.ClaimActions.MapJsonKey(ClaimTypes.NameIdentifier, "sub");
})