If you are using Varnish and ESI with a Symfony application and need to profile not only the master request but with ESI requests included, don't announce your ESI support, Symfony will fallback to internal sub requests.

default.vcl

sub vcl_recv {
  if (req.http.X-Blackfire-Query && client.ip ~ profile) {
      //set req.backend_hint = backend1; // if you want to disable loadbalancer to profile (aka only 1 backend needs blackfire extension
      return (pass);
  } else {
    // Add a Surrogate-Capability header to announce ESI support.
    set req.http.Surrogate-Capability = "abc=ESI/1.0";
  }
   
}