Let's begin defining our happy scenario by writing the feature file:

Scenario: Valid Input

  Tests that the 'Register' button is enabled when valid values are provided, and that upon successful registration, the UI display will display the message "You've been registered successfully"

  When user types in a valid email in the "#email" element
  And user types in a valid password in the "#password" element
  Then the "#register-button" element should not have a "disabled" attribute

  When user clicks on the "#register-button" element
  Then the "#registration-success" element should appear within 2000 milliseconds