Content-Security-Policy-Report-Only Cannot Be Declared Without report-uri Directive
Content-Security-Policy-Report-Only cannot be declared without
report-uri directive, because of that it will send the violations to the defined URL.
Content-Security-Policy-Report-Only: script-src 'self'; report-uri https://www.example.com;
Actions To Take#
If you want to use one of the CSP in report only mode, you should declare with a report-uri