Capybara - NameError: uninitialized constant Capybara::TimeoutError

I am creating integration tests for my rails application.

The application I am working to is a little slow. In my test, I execute a certain action within the website (a "saving" - which reloads in the end the page) and the following capybara action runs before the page is actually reloaded.

I cannot use "sleep (seconds)" as this freezes the "reloading" itself.

So I wanted to give a try to this github idea: http://ift.tt/2abMF4v

but I get the following error:

NameError: uninitialized constant Capybara::TimeoutError

Can someone tell me why I get this error and what does it mean?