When we define the document attribute icons with the value font the FontAwesome fonts are loaded in the generated HTML page. In the head section of the HTML document a link element to the FontAwesome CSS on https://cdnjs.cloudflare.com/ajax/libs is added. Also when we use the highlight.js or Prettify source highlighter a link to the Javascript files on the cdnjs.cloudflare.com server is generated. We can change the value of the scheme from https to http by setting the attribute asset-uri-scheme to http. Or we can leave out the scheme so a scheme-less URI is generated for the links. A scheme-less URI provides the benefit that the same protocol of the origin HTML page is used to get the CSS or Javascript files from the cdnjs.cloudflare.com server. Remember this might provide a problem if the HTML page is opened locally.

In the next sample Asciidoc markup we change the scheme to http:

:asset-uri-scheme: http
:icons:font

== Asset URI Scheme

Sample document.

In the generated HTML we see the new scheme value:

Now we leave the value of the `asset-uri-scheme` attribute empty:

:asset-uri-scheme:
:icons:font

== Asset URI Scheme

Sample document.

The generated HTML now contains a link to the FontAwesome CSS with a scheme-less URI:

Written with Asciidoctor 1.5.0.

Original article.