Steps:

1. 1. Go to Test Step Custom Fields.
   2. Cerate new Test Step Custom Field
   3. in name filed add XSS Payload. "><img src=x onerror=alert(1)>
   4. After creating you will notice a column in the Custom Fields table called "Actions". Next to the Custom Fields you created there are three points. Click on it and select "Required"
   5. Now go to Test Case Importer Setup
   6. in CSV Source File Field Upload CSV file and click in next
   7. Now in import to Project filed select project.
   8. Now when click Next XSS Payload reflected on you.