Here's the /libs/ directory on CodePen.
Sorry that wasn't very accessible, but the point is: yes, many. Those aren't all used on every page of CodePen, and there might be some stuff we've stopped using in there, but I'd say most of it is used.
That doesn't include our latest thinger we're working on that is in React/Redux and the smattering of libs that come with that.
I'd prefer nobody in the world picks a JavaScript framework based on what I use. I'm a follower in that regard, and definitely not qualified to be a trendsetter.