Account menu not working in sample_app of rails 3.2 version

I am reading chapter 8 (sign in, sign out) from michael hartl Ruby on
Rails book.

I have deployed my sample_app to heroku. When I check heroku links, In
that account menu not working, drop down list is not coming.

what will be reason for this?Could anyone can help me in this?

Kind regards.

http://www.catb.org/esr/faqs/smart-questions.html

Hassan Schroeder wrote in post #1146084: