We are currently evaluating UDM4 in the context of Chrome. Chrome is still a beta release, so we aren't officially supporting it at this point, but there do seem to be several problems with its javascript engine that will need to be addressed in the UDM4 code base.
So far, this seems to be limited to horizontal menus, but we are looking into the issue. If you haven't already, please subscribe to the newsletter for the latest updates.
The problem is the site tests navigator.vendor for "Apple Computer, Inc."
Chrome now gives "Google Inc."
I recommend modifying the site code to instead test for WebKit in the user agent
string (which is the rendering engine used in both safari and chromium:
var isWebKit = /AppleWebKit/.test(navigator.userAgent);
// um.073=0. In chromium um.ss=true so this if block is entered. Whereas in safari
um.ss=false so the block is not entered. The block does some webkit unsupported style
operations which throw DOM exception in both chromium and safari.