When you are using :source-highlighter: highlightjs the generated html from asciidoctor will use "protocol relative URLs" (and not include anything in front of the two forward slashes in a url/src/href attribute).
So how do we force asciidoctor to prefix with "http:"?
or even better:
How do we substitute "//cdnjs.cloudflare.com/ajax/libs/" with "highlight.js" to use local installation?