Why are JavaScript files read from an external URL?
You're confusing the attributes on that tag.


class="js" is a class name, it has nothing to do with loading javascript from external sources. It's simply added to the tag by javascript when the page loads so that any process (css usually) that needs to know about it can easily tell whether javascript is enabled or not.
The xml:* attributes are required to identify the document as XHTML. They're not related to javascript in any way.


There's no need to change anything, unless you want to get a bit more up-to-date and install a theme that produces an HTML5 document.