Chrome closes dialog box immediately

Chrome closes dialog box immediately

I have a problem with an application I am starting to develop.  I want to get a logon dialog box to come up over the first page, which gets the user to logon.  It works in Firefox (Iceweasle - I am running Debian) but not in Chrome.

This fsFiddle demonstrates the problem

http://jsfiddle.net/akc42/ZmcP8/

I have spent some time in the Chrome debugger, and it appears to be getting a popstate event which tells the framework to go back to the first page.  I just can't figure out what is causing this event to trigger.