The step we used in the past (Then "foo" should not be visibile) doesn't reliably work in Selenium features.
I overhauled the entire step so it uses Javascript to detect visibility in Selenium.
The step has support for jQuery and Prototype projects, so it should be a drop-in replacement for all your projects.
For Rack::Test the step no longer uses XPath so you should be able to understand it when you are not a cyborg :)
There were some other cards detailing alternative steps to detect visibility. I deleted all these other cards since the updated step should work in all situations. If you find a problem with the updated step, please work with me to maintain it. We should only have one standard step for the same thing.

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

Updated: Capybara: Check that a page element is hidden via CSS