JSON formatting in the browser (missing headers)?

https://codeigniter.com/user_guide/outgo...-reference

PHP Code:

return $this->setResponseFormat('json')->respond(['error' => false]); 


respond($data[, $statusCode=200[, $message='']])
Parameters:
$data (mixed) – The data to return to the client. Either string or array.
$statusCode (int) – The HTTP status code to return. Defaults to 200
$message (string) – A custom “reason” message to return.