Interesting, what version of Firefox is this? You can see in the CSP that &#x27;self&#x27; is a defined keyword for both the script-src and style-src directives: <a href="https:&#x2F;&#x2F;report-uri.io&#x2F;home&#x2F;analyse&#x2F;https%3A%2F%2Fsecurityheaders.io%2F" rel="nofollow">https:&#x2F;&#x2F;report-uri.io&#x2F;home&#x2F;analyse&#x2F;https%3A%2F%2Fsecurityhea...</a>