html desktop notification file complete html?

HTML5 desktop notifications have an HTML option where we can show an HTML page inside a notification. What I was wondering was, should the page to be shown inside the notification be a 'complete' html page or just a bunch of nodes?

By 'com开发者_高级运维plete' I mean, should it have a doctype and head, body, and html tags? What about external JavaScript and CSS files? I have been showing it as a bunch of nodes for sometime and it does not seem to have any problems that way, but now as the app develops, the page is getting more sophisticated and I now need to move the CSS and JavaScript to their own external files.

According to W3C specification it is a separate window and therefore the content has to be complete html document