More updates ....
I originally added the cloneNode(true) code when I couldn't even get the Ch. 3 Hello / ping example to work; that addition solved it. However, since I've added a forward and reverse proxy for the http-bind from my web server to my xmpp server (ejabberd), I find I don't need flXHR. And removing that from Ch.3 and Ch.6 examples made both of them work better.
... Ch. 6 now has a "better error". Chrome gives the easiest to read error backtrace:
/~fafhrd/foobar/scripts/strophe.js:1505Uncaught TypeError: Object <li id='foxtrot-quarmall-apt'><div class='roster-contact offline'><div class='roster-name'>firstname.lastname@example.org</div><div class='roster-jid'>email@example.com</div></div></li> has no method 'find'
So ... 1) Proxy in web server to xmpp server, good; flXHR, bad; 2) everything works in most browsers, 'cept for adding contacts to your list in Ch. 6 "Gab".