I don't have an answer for you, but I found a few clues that the developers of UDM4 might be able to use. First of all, your web page works just fine in Firefox. However, when I opened it in Internet Explorer, I got the same error that you did. When I clicked "yes" on the "would you like to debug" alert box, that opened up Visual Studio on my PC and highlighted the following code in youarehere.js:
As I said, it's just a clue but perhaps the UDM4 developers will be able to interpret it and fix the problem.