I'm trying to evaluate several open source applications which display rather elaborate browser output generated by JavaScript. That is, when I load a page and then display the source, all I see is the bare skeleton of an HTML page with a reference to a .js file. All of the content comes from the JavaScript -- not just variable content, but the fixed parts as well. Firebug shows a little more detail, but not enough to be useful.

This makes my job very difficult, because an application's flexibility in terms of CSS changes, etc., is a big part of what I need to evaluate. I can do this with a great deal of effort by learning the internals of each application or I can do it quickly and easily by studying a few samples of generated HTML... except that I can't see the generated HTML, because in these applications it's invisible.

Is there a way to see the "HTML" for the entire content of one of these pages?