The latest version of the compojoom library is trying to include 2 javascript files from a CDN that no longer appears to be up.
In /libraries/compojoom/html/behavior.php, lines 59-60
JHTML::_('script', 'https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js');
JHTML::_('script', 'https://oss.maxcdn.com/libs/respond.js/1.3.0/respond.min.js');
I have replaced these links with another CDN's equivalent. I wanted to bring this to your attention as I'm sure I'm not the only one experiencing this. Not sure what happened to maxcdn, but it appears to have closed up shop.