There are following below methods to add Referrer Policy Security Header in Apache or NGINX or .HTACCESS
[1] How to add in Nginx configuration file There are following code need to add in Nginx configuration file add_header set Referrer-Policy "strict-origin-when-cross-origin"; [2] How to add in Apache configuration file There are following code need to add in Apache configuration file header always set Referrer-Policy "strict-origin-when-cross-origin" [3] How to add in .htaccess file There are following code need to add in .htaccess configuration file <IfModule mod_headers.c> Header set Referrer-Policy "strict-origin-when-cross-origin" <IfModule mod_headers.c>
HTTP Security Headers Checker Tool
https://www.site2info.com/sitesecurity.php
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