If you would like to set up a split test and the target URLs contain optional parameters, you will have to use the option “regular expression” to set up your redirection.
Suppose that you want to redirect the page http://www.example.com to http://www.example.com/variation. You also use Google Analytics tracking parameters to track your traffic acquisition sources. You therefore want the URL http://www.example.com/?utm_medium=email&utm_source=newsletter to redirect to http://www.example.com/variation?utm_medium=email&utm_source=newsletter.
To achieve this, you must set up the test in the same way as we present below, ticking the box “Transfer url parameters”.