How to properly receive the DOMContentLoaded event from an XUL iframe?

Question

I\'m working on a minimal Firefox extension that loads a web page into an XUL iframe. (I also tried the html:iframe, but met identical results.) The page may

Answer 1

Does the issue happen when you open your XUL page through the Firefox menu > Web Developer > Error Console > open("chrome://yourpage.xul", "", "width=640,height=480");? The browser that is beneath the location bar is marked as content-primary, which makes the pages in there run with restricted privileges, regardless of the protocol that the page is coming from (this is counter-intuitive, granted). It could be what's causing your issue, but I'd be unable to tell you the exact reason why, unfortunately.

The next step for such subtle issues involves connecting to irc.mozilla.org#developers and asking about your problem when the west coast is awake :).