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/@mui/utils/unsupportedProp/unsupportedProp.js

@@ -0,0 +1,10 @@
+export default function unsupportedProp(props, propName, componentName, location, propFullName) {
+  if (process.env.NODE_ENV === 'production') {
+    return null;
+  }
+  const propFullNameSafe = propFullName || propName;
+  if (typeof props[propName] !== 'undefined') {
+    return new Error(`The prop \`${propFullNameSafe}\` is not supported. Please remove it.`);
+  }
+  return null;
+}