The BFF silent login endpoint can be customized by implementing the ISilentLoginService or by extending DefaultSilentLoginService, its default implementation.
ProcessRequestAsync is the top level function called in the endpoint service and can be used to add arbitrary logic to the endpoint.
For example, you could take whatever actions you need before normal processing of the request like this:
public override Task ProcessRequestAsync(HttpContext context)
{
// Custom logic here
return base.ProcessRequestAsync(context);
}