The latest version of React DevTools offers a powerful new tool, the Profiler tab, to detect and diagnose performance issues in React apps. The Profiler helps identify expensive renders and too many commits to the DOM, which can cause performance issues. In this case study, the author used the Profiler to quickly diagnose and fix a known issue with server logs on app.netlify.com, which were causing unresponsive UIs for users. By analyzing the Profiler data, the author was able to pinpoint the problematic component, `DeployLogContainer`, and implement a debounced state update function to reduce unnecessary commits to the DOM, resulting in improved performance and reduced render times.