Poltergeist supports URL blacklisting which allows you to prevent scripts from running on designated domains. If you are experiencing slower run times, consider creating a URL blacklist of domains that are not essential to your testing environment, such as ad networks or analytics.page.driver.browser.url_blacklist = ['http://www.example.com']
Make sure you set it before each running test, because this setting’s cleaned up when capybara does reset.
for example like so:
config.before(:each, js: true) do page.driver.browser.url_blacklist = ["http://use.typekit.net"] end