Rails system tests for multiple screen sizes

Rails system tests simulate a user's actions in a web browser so it's akin to the app's real world usage. In a responsive app, this means testing on multiple screen sizes as well.Capybara, the tool used by system tests under the hood, has a method to resize the current window during a test run. But, since the tests are not run in a set order, any test that resizes the window needs to restore the size after it's done. Otherwise, subsequent tests run in that window could fail.