This is my csp reporter script based on the script provided there https://mathiasbynens.be/notes/csp-reports

• Download & copy this script to the webroot
• Edit the script and configure the $recipients and $subject variables
• Add to your CSP rule: report-uri /csp-reporter.php

The backlist allows you to block reports from beeing send to you.

Basicly now this is a per domain and per directive blacklist.

Here is a example:

'style-src' => [
	'adblockers.opera-mini.net',
],

This configuration would block all emails where our csp reporter get a hit because of opera's addblocker injecting style files into your site.

If you need a Joomla Integration for CSP and other HTTP Headers you can take a look into my plugin: plg_system_httpheader. As of Joomla 4.0 this plugin is shipped with the core distribution as drop in replacement: Pull Request #18301