ReferenceError: Can't find variable: Enabler, Google Web Designer Published Locally

Question

I have received several ads exported from the Google Web Designer tool in the folder format:

/Ad-Name/
  |-index.html
  |-image.jpg
  |-overlay.png

However when I open index.html in Safari 14.1.2 nothing loads, and when I check the console I find the error:

ReferenceError: Can't find variable: Enabler

Which points me to this line:

Enabler.addEventListener(studio.events.StudioEvent.EXPAND_START, this.H);

I assume it should be coming from this script tag on line 2000 something:

<script data-source="https://s0.2mdn.net/ads/studio/Enabler.js" data-exports-type="gwd-google-ad" src="https://s0.2mdn.net/ads/studio/Enabler.js"></script>

Even when I move it above the line where the Enabler object is used first, nothing changes.

The most darndest thing is that it did work for about five minutes earlier today. Because of this I thought there might be some kind of cache issue but I get the same error after clearing all my data.

Reading the docs has not helped.