Hm. May be something with my system, but I'm getting weirdness in firefox now as well. I think its the same behavior, but FF handles it differently in that it displays the page code versus downloading it, like happens in Chrome. In any event, here is what I get when I click on a red folder in FF:
Refreshing the page applies the styles and everything displays normally.
I will try and do some troubleshooting with web console in FF and let you know what I find.