So firefox allows you to view the browser's dom, via the browser developer toolbox that you have to enable separately.
In the dom, the currently opened pages are contained in browser elements, and the currently viewed one has the attribute "primary=true". Under this element there is a #document element which has the page's actual html content in it.
What i want to achieve, is to get the current page element and view it's content. I've tried this:
document.querySelector('browser[primary=true]');
Which returns the correct browser element, except it has no children, unlike in the inspector. So I can't access the page's content through that.