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/react-redux/es/utils/shallowEqual.js

@@ -0,0 +1,27 @@
+function is(x, y) {
+  if (x === y) {
+    return x !== 0 || y !== 0 || 1 / x === 1 / y;
+  } else {
+    return x !== x && y !== y;
+  }
+}
+
+export default function shallowEqual(objA, objB) {
+  if (is(objA, objB)) return true;
+
+  if (typeof objA !== 'object' || objA === null || typeof objB !== 'object' || objB === null) {
+    return false;
+  }
+
+  var keysA = Object.keys(objA);
+  var keysB = Object.keys(objB);
+  if (keysA.length !== keysB.length) return false;
+
+  for (var i = 0; i < keysA.length; i++) {
+    if (!Object.prototype.hasOwnProperty.call(objB, keysA[i]) || !is(objA[keysA[i]], objB[keysA[i]])) {
+      return false;
+    }
+  }
+
+  return true;
+}