embedding with debugging support

Hello,

My name is Chris and I would like to embed Mozilla into a C++ app.
I have managed to do this, but I need to have some debugging support (for html, javascript).

The only way I know of, is to try to embed some extensions like venkman/dom inspector.

The documentation I found for this seems old/confusing. I was not able to embed these after reading this link:
https://developer.mozilla.org/en/XULRunner_tips

Is there any other information available?

Note: I do not use a xul app and I am also not familiar with xul. So far, all I need is a webbrowser window in which I could click and say 'Inspect DOM, debug
javascript....", something like this.

  Thanks a lot
      Chris