Service messenger detail

Computed Definition =>

array:4 [
  "class" => "Drupal\Core\Messenger\Messenger"
  "arguments" => {#1571
    +"type": "collection"
    +"value": array:2 [
      0 => {#1569
        +"type": "service"
        +"id": "Symfony\Component\HttpFoundation\Session\Flash\FlashBagInterface"
        +"invalidBehavior": 1
      }
      1 => {#1568
        +"type": "service"
        +"id": "page_cache_kill_switch"
        +"invalidBehavior": 1
      }
    ]
  }
  "arguments_count" => 2
  "alias" => "Drupal\Core\Messenger\MessengerInterface"
]

Instance =>

Drupal\Core\Messenger\Messenger {#264
  #flashBag: Symfony\Component\HttpFoundation\Session\Flash\FlashBag {#196
    -name: "flashes"
    -flashes: & []
    -storageKey: "_symfony_flashes"
  }
  #killSwitch: Drupal\Core\PageCache\ResponsePolicy\KillSwitch {#234
    #kill: false
  }
}