Cross-site Referrer Leakage through usage of strict-origin in Referrer-Policy
Invicti detected that origin leakage is possible due to use of strict-origin
in the Referrer-Policy implementation.
If a comma-separated referrer-policy is specified in the header, fallback policy is used only if the browser does not support the set referrer-policy, which may cause Cross-site Referrer Leakage.
Origin (Domain) information can be leaked through Referer
header, if a request occurs to a site either has same or a higher protocol.
If leakage of the origin is a problem for the site, see all available options by using links in External References and use a secure one.