Referrer-Policy HTTP header

The Referrer Policy HTTP header sets the parameter for amount of information sent along with Referrer Header while making a request.
Referrer policy is used to maintain the security and privacy of source account while fetching resources or performing navigation. 
This is done by modifying the algorithm used to populate Referrer Header. 

Referrer Policy can be delivered for a request through various methods. 
It can be done by simply using the HTTP header or the meta element in HTML which takes referrer keyword as value that in turn allows referrer policy setting through markup or using the referrerpolicy content attribute in HTML. 
CSS consults the referrer policy of owner document when style attribute is used and policy can be over-written for external stylesheets which have default value of no-referrer-when-downgrade. 

• On the Web site parameter, choose Options tab.
• Click on the Rule button inside the Header rules row

• Click on “New rule” button.

• Set a description of your rule.
• Add “Referrer-Policy” inside HTTP Header Field

Select of these items as Content :

• no-referrer : 
  This sends no referrer information along with the request made.
• no-referrer-when-downgrade : 
  This sends complete URL information to a potentially trustworthy URL from modern HTTPS State or from not modern HTTPS state to any origin . Information is sent for HTTPS -> HTTPS and HTTP -> HTTPS transition . 
  This is the default Referrer-Policy.
• origin : It only sends the origin value of the request client when making either same-origin (same website) or cross-origin (different website) requests.
• strict-origin : 
  This only sends origin information to potentially trustworthy URL from modern HTTPS State or from not modern HTTPS state to any origin.
• origin-when-cross-origin : 
  It sends complete URL information when making requests on same origin but only origin information when making cross-origin requests.
• strict-origin-when-cross-origin : 
  It sends complete URL information when working on request from same origin. It sends only origin information to potentially trustworthy URL from modern HTTPS State or from not modern HTTPS state to any origin. No referrer information is sent to a potentially non-trustworthy URL.
• same-origin : 
  It sends referrer information when origin is on same website but no information is sent for cross origin.
• unsafe-url : 
  It sends complete URL information irrespective of any criteria.

After finish, click on “Apply parameters to the system” button to make header in production mode