Exactly, never ALLOW, always BLOCK. See my original step-by-step.

I recommend that you always BLOCK and send these out-of-date content delivery networks (CDNs) to the restricted list.

Technically, if you allow the "defunct" CDN address, you could get a cross-attack if a malicious force takes over that CDN address and injects bad code, like data-stealing code, virus, etc.

This not only affects Quickbooks but other Intuit programs like Lacerte, etc.