Add a referral code to the url: ?referral_code=yourreferralcode and refresh the page to save the code in a cookie.
Click here to open a new window without the referral code in the url. Check the text field below to see if the it is saved and passed on.
If you close the browser and visit this page again (without the referral code in the url) the code should appear in the text field below.
The button links to the portal and adds the referral code to the url.