Adding own files to template

[Moritz-Staat]

I would like to use an external file in my template. When integrating, the error message "Refused to load the image 'https://domain.com/images/link5.png' because it violates the following Content Security Policy directive: "img-src 'self' blob: data: data:"." appears. Is there a way to get round this?
@cfoellmann