Answer
Trusted domains control where your HelperHat widget is allowed to appear. If you add domains, HelperHat only loads on matching sites. HelperHat normalizes domains, ignores a leading www., and allows matching subdomains. For example, adding example.com can allow example.com, www.example.com, and subdomains such as shop.example.com. If you leave the list empty, the install code is not restricted by domain, so adding your official domains is recommended.