Recently upgraded from a 2.0.8 release to 2.1.3. When my client tried to duplicate a resource via right click on the resource tree using IE8, nothing would happen. The context menu would simply stay on the page. Everything worked fine in other browsers.
After digging, found this in modext-min.js:
console.log(C.attributes)
Once I removed this, everything worked again. It's also in modext.js as:
console.log(node.attributes);
I'm guessing these should be removed.