Setup:

1. Blazor WASM application with configured authentication for Azure B2C – fully working (login process and getting and sending access token for another resource – Azure Functions app)
2. Azure Functions application (isolated) – getting access token in HTTP header
3. B2C tenant with configured app registrations and scopes

How to validate access token and implement authorization for my Functions as well as getting user data from a token?

I have read that ASP.NET mechanism is not working for Azure Functions, and I tried that, but I get that a user is not authenticated.