Capybara's first gem release was in 2009. At that time, JavaScript was not required for many popular web pages, and a popular approach to web development was "unobtrusive JavaScript", which meant that the basic functionality of a web page was still available without JavaScript. The most popular framework for JavaScript was jQuery and single-page web app frameworks like Angular.js or React were not in wide use. In the intervening years, web pages have been steadily replaced by web apps, which require JavaScript for all functionality. The single-page web application is a very popular architecture and many frameworks exist to support it.
The reason for this history lesson is to put in context the choices we are going to make about how we use Capybara. The easiest way to use Capybara and the first thing documented in its README
is to let Capybara start our web app automatically, allowing anything in the app to be mocked. To interact with the web...