array:1 [ // app/Http/Controllers/DropboxController.php:61
  "error" => "invalid_client: Invalid client_id or client_secret"
]

[] // app/Http/Controllers/DropboxController.php:19

Illuminate\Filesystem\FilesystemManager {#1831 // app/Http/Controllers/DropboxController.php:43
  #app: Illuminate\Foundation\Application {#2 …40}
  #disks: []
  #customCreators: array:1 [
    "dropbox" => Closure(Application $app, array $config) {#1680
      class: "App\Http\Controllers\DropboxController"
      this: App\Http\Controllers\DropboxController {#1844 …}
    }
  ]
}