Avast Web Shield Blocking CORS on safe website

We have Avast Business deployed and have policies for web guard / web control for white/blacklisting sites. we use Fedex dot com (no issues accessing the fedex site in general), however if we try to login to our fedex account , before we are prompted to login, we get an error in the FedEx site that it can’t establish a connection (not an Avast prompt). In looking at the web-console in the browser, we can see that it’s a CORS issue where the fedex login is requesting something from cross domain, and that connection is not working. If we turn off Avast, it connects fine. Something that the fedex login page is asking for from an outside domain must be being blocked. We’ve tried to decipher what it is, but have had no luck.

I need to know how to enable my users to login to their fedex account without having to disable Avast