Grabbed dndbeyond's source code

```
~/go/bin/sourcemapper -output ddb -jsurl https://media.dndbeyond.com/character-app/static/js/main.90aa78c5.js
```

ddb_main/node_modules/@babel/polyfill/lib/index.js

@@ -0,0 +1,13 @@
+"use strict";
+
+require("./noConflict");
+
+var _global = _interopRequireDefault(require("core-js/library/fn/global"));
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { "default": obj }; }
+
+if (_global["default"]._babelPolyfill && typeof console !== "undefined" && console.warn) {
+  console.warn("@babel/polyfill is loaded more than once on this page. This is probably not desirable/intended " + "and may have consequences if different versions of the polyfills are applied sequentially. " + "If you do need to load the polyfill more than once, use @babel/polyfill/noConflict " + "instead to bypass the warning.");
+}
+
+_global["default"]._babelPolyfill = true;