Introducing the HEAD feature for each page(iframe) of your book!
This feature is more or less self-explanatory, so not much to talk about here. All you have to do is to put whatever is required inside the HEAD input box of the page and those resources will be automagically loaded inside the <head> of the page’s iframe. That’s it.
Content delivery networks (CDNs) allow libraries to be cached across different websites that use the same version of the resource, and help reduce latency by serving the files from a server that is physically near the user’s location.
We thought what if e-books could take advantage of CDNs too. Utilize the libraries offered over CDN to render clever and highly optimized content to readers, just like the websites do!
Enter HEAD feature (See figure above).
There are several CDN services out there. Two notable ones that we particularly like are the Cdnjs and jsDelivr, but there are others too and feel free to use anyone of them, as long as the providing network is able to serve resources over https.
Note, all external resources must use secured http i.e. https only.
We have left the HEAD feature pretty much vanilla to keep it simple and flexible about what can be added up there: Meta tags, scripts, stylesheet or perhaps a Llama if it helps to get the job done.