I have a newish Rails 4 app which contains no custom Javascript - the folders app/assets/javascripts, lib/assets/javascripts and vendor/assets/javascripts are all empty (apart from app/assets/javascripts/application.js).

When I click around the app I keep getting the error jquery-ujs has already been loaded! in the JS console. It happens every time I hit the back button, and sometimes when I click a normal link (although I can't make it happen consistently.)

application.js:

//= require jquery

//= require jquery_ujs

//= require twitter/bootstrap

//= require turbolinks

//= require_tree .

When I remove turbolinks from application.js, I stop getting the error... so turbolinks appears to be the culprit.

Is this a bug with turbolinks, or am I doing something wrong?

Here's my Gemfile:

source 'https://rubygems.org'



ruby '2.0.0'



gem 'rails', '4.0.0'



gem 'active_model_serializers'

gem 'aws-sdk'

gem 'bootstrap-sass-rails'

gem 'coffee-script-source', '1.5.0'

gem 'coffee-rails', '~> 4.0.0'

gem 'devise'

gem 'factory_girl_rails', '4.1.0'

gem 'figaro'

gem 'font-awesome-sass-rails'

gem 'jbuilder', '~> 1.2'

gem 'jquery-rails'

gem 'paperclip'

gem 'paperclip-meta', github: 'y8/paperclip-meta'

gem 'pg'

gem 'sass-rails', '~> 4.0.0'

gem 'turbolinks'

gem 'uglifier', '>= 1.3.0'



group :production do

  gem 'rails_12factor'

end



group :doc do

  gem 'sdoc', require: false

end



group :test do

  gem 'capybara', '2.1.0'

end



group :development, :test do

  gem 'childprocess', '0.3.9'

  gem 'debugger'

  gem 'faker', '~> 1.2.0'

  gem 'json_spec'

  gem 'rspec-rails'

  gem 'rspec-mocks'

end



group :development do

  gem 'annotate'

  gem 'hirb'

  gem 'wirb'

end

Changing around the order of the requires in application.js doesn't seem to help either.