title: capybara with :js => true very slow
body: <p>when I toggle :js => true on my examples, takes too long very long to come up and run the first test, then becomes acceptable peformance</p>
  
  <p>this sample running in  0.36722 seconds without :js, and 58.15 seconds with :js => true</p>
  
  <pre><code>require 'spec_helper'
  
  include UserAbilitiesHelper
  
  describe "Customer Task Pages" do
  
    subject { page }
  
    describe "side panel with the history of the tasks related to customer" do
      before do
        visit root_path()
      end
  
      it { sould have_content(I18n.t("customers.tasks.side.title")) }
  
  
    end
  
    describe "side panel with the history of the tasks related to customer" do
      before do
        visit root_path()
      end
  
      it { sould have_content(I18n.t("customers.tasks.side.title")) }
  
  
    end
  
  
  end
  </code></pre>
  
  <p>my Gemfile</p>
  
  <pre><code>source 'https://rubygems.org'
  
  gem 'rails', '3.2.5'
  gem 'pg', '0.12.2'
  
  gem "meta_search"
  
  # Bootstrap and layouting
  gem 'bootstrap-sass', '2.0.3'
  gem 'will_paginate', '3.0.3'
  gem 'bootstrap-will_paginate', '0.0.6'
  gem 'rails3-jquery-autocomplete'
  
  #test support
  gem 'faker', '1.0.1'
  
  #login rules
  gem 'devise'
  gem 'cancan'
  
  #criptar
  gem 'bcrypt-ruby', '3.0.1'
  
  #BR
  gem 'brazilian-rails'
  gem 'rails-i18n'
  
  group :development do
      gem 'annotate', '~&gt; 2.4.1.beta'
      gem 'nested_scaffold'
  end
  
  group :development, :test do
    gem 'rspec-rails', '2.10.0'
    gem 'guard-rspec', '0.5.5'
    gem 'guard-spork', '0.3.2'
    gem 'spork', '0.9.0'
    gem 'ruby-debug19'
    gem 'linecache19'
    gem 'factory_girl_rails', '1.4.0'
  end
  
  # Gems used only for assets and not required
  # in production environments by default.
  group :assets do
    gem 'sass-rails',   '3.2.4'
    gem 'coffee-rails', '3.2.2'
    gem 'uglifier', '1.2.3'
  end
  
  gem 'jquery-rails', '2.0.0'
  
  group :test do
    gem 'capybara', '1.1.2'
    gem "launchy"
    gem 'ZenTest'
    #MAC OS Especific
    gem 'rb-fsevent', '0.4.3.1', :require =&gt; false
    gem 'growl', '1.0.3'
  
    #Cucumber
    gem 'cucumber-rails', '1.2.1', require: false
    gem 'database_cleaner', '0.7.0'
  end
  
  group :production do
    #gem 'pg', '0.12.2'
  end
  </code></pre>
  
  <p>running with</p>
  
  <pre><code>bundle exec rspec
  </code></pre>
  
  <p>An example any</p>
  
  <pre><code>Bruno-Guerras-MacBook-Pro:railstutorial brunoguerra$ bundle exec rspec spec/requests/authentication_pages_spec.rb 
  No DRb server is running. Running in local process instead ...
  WARNING: Nokogiri was built against LibXML version 2.7.8, but has dynamically loaded 2.7.3
  .....................
  
  Finished in 6.07 seconds
  21 examples, 0 failures
  Bruno-Guerras-MacBook-Pro:railstutorial brunoguerra$ bundle exec rspec spec/requests/authentication_pages_spec.rb 
  No DRb server is running. Running in local process instead ...
  WARNING: Nokogiri was built against LibXML version 2.7.8, but has dynamically loaded 2.7.3
  ............F........
  
  Failures:
  
    1) Authentication authorization for non-signed-in users when attempting to visit a protected page after signing in should render the desired protected page
       Failure/Error: page.should have_selector('title', text: 'Edit user')
         expected css "title" with text "Edit user" to return something
       # ./spec/requests/authentication_pages_spec.rb:65:in `block (6 levels) in &lt;top (required)&gt;'
  
  Finished in 1 minute 14.18 seconds
  21 examples, 1 failure
  
  Failed examples:
  
  rspec ./spec/requests/authentication_pages_spec.rb:64 # Authentication authorization for non-signed-in users when attempting to visit a protected page after signing in should render the desired protected page
  Bruno-Guerras-MacBook-Pro:railstutorial brunoguerra$
  </code></pre>
  
  <p>thanks</p>