Locating the source of Forbidden message When I login I see these "Forbidden" messages. How to track the source of this message?

Also I've enabled these settings:

error_reporting(E_ALL);
ini_set('display_errors', TRUE);
ini_set('display_startup_errors', TRUE);
I started disabling modules one by one and rest_auth was actually causing it though it was  not being used. Simply disabling solved it. And yes it does not contain any word "forbidden".