Changing the onsiteURL RegExp when setting up reference sites in AEM 6.5 forms

I want to set up and study the reference sites for AEM forms 6.5 in my local AEM quickstarts. I'm slowly working my way through the instructions found here and I've come to a step labelled "Override default XSS configuration." This directs me to replace an almost 4 kilobyte, painfully complex regular expression with one that's vastly shorter. Is this actually correct, or is this step left over from a previous version?

Thank you,

Tony