Say you have a source XML file with ?xml-stylesheet PI, so when you load it into a browser it will be transformed through the stylesheet. Let's say the source XML file was transformed to HTML and is displayed. All good.

Now the HTML contains a script (javascript) element to do stuff. Is there any way, standard or secret, by which one could get back to the original source XML of the current document?

I did not find one, so I have the XSLT output the source into a head/script element with id="source" and type="text/xml". But when I load that with

document.getElementById("source").firstChild 

I get text not the actual element. If I do DOMParser parseFromString, I get a namespace prefix undeclared error, because XSLT didn't output the namespace prefixes that were already declared under this source node.

Perhaps there is some way with a different HTML element that it actually reads the content as DOM nodes, with all the namespaces, not as a mere text node.

I have tried to use other elements than script, for example, there is a tag called <xml> in HTML, which you can use to embed XML. And when I use this, the

document.getElementById("source").firstChild 

actually gets me an element, not just a text node.

However that element is not namespace aware, so it does not know anything about the xmlns declaration that were already made outside and the XSLT thus did not output again.

Ideally I could just get to the source XML without having to embed it in the HTML. But if I have to embed it, how can I force all namespaces to be declared again?