Almost a year ago, Scott Helme, creator of securityheaders.io and report-uri.com, wrote a blogpost on a not well known http header: Referrer-Policy.

Regular readers will know how fond I am of the existing security headers so it's great to hear that we're getting another! Referrer Policy will allow a site to control the value of the referer header in links away from their pages.

https://scotthelme.co.uk/a-new-security-header-referrer-policy/