>Could you give us a link..
Since you asked, of course, it's working. Firebug is now displaying everything. I don't know why it's doing that now or how to make sure it will continue.
I'm opening Firebug by clicking the bug icon on the toolbar. I used to click the downarrow and select Firebug UI Location > Detached. For some reason that isn't working now, but it doesn't seem to affect anything else.
The example I'm working with now is the Swagger demo, for example, at http://petstore.swagger.wordnik.com/#!/user.
Although the source code in Firebug is complete (now) the source code in Firefox is very scanty. When I posted my question the source code in Firebug was similar. In the source code from Firefox, the body contains:
A <form> embedded in two <div>s. This corresponds to the green bar at the top of the page.
The following code, which generates everything else:
[INDENT]<div id="message-bar" class="swagger-ui-wrap">
<div id="swagger-ui-container" class="swagger-ui-wrap">[/INDENT]
Ginger: I did try it in Chrome, and got essentially the same results. I haven't tried again since Firebug started working for me.