Set
Header set Referrer-Policy “no-referrer”
in your .htaccess
On my installation it looks like this:
<IfModule mod_env.c>
# Add security and privacy related headers
Header set X-Content-Type-Options "nosniff"
Header set X-XSS-Protection "1; mode=block"
Header set X-Robots-Tag "none"
Header set X-Download-Options "noopen"
Header set X-Permitted-Cross-Domain-Policies "none"
Header set Referrer-Policy "no-referrer"
SetEnv modHeadersAvailable true
</IfModule>