The “Same Origin Policy” is introduced for security reason, and it ensures that content of your site will never be accessible by a script from another site. As per the policy, any code loaded within the browser can only operate within that website’s domain.
To avoid “Same Origin Policy” proxy injection method is used, in proxy injection mode the Selenium Server acts as a client configured HTTP proxy , which sits between the browser and application under test and then masks the AUT under a fictional URL
