Grabbed dndbeyond's source code

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

ddb_main/hooks/useUserName.ts

@@ -0,0 +1,19 @@
+import { useState, useEffect } from "react";
+
+import { getUserDisplayName } from "../helpers/userApi";
+
+const useUserName = () => {
+  const [userName, setUserName] = useState<string | null>("");
+
+  useEffect(() => {
+    getUserDisplayName()
+      .then(setUserName)
+      .catch(() => {
+        setUserName(null);
+      });
+  }, []);
+
+  return userName;
+};
+
+export default useUserName;