In Q3 2025, our team’s React 19 migration caused a 47% spike in Lighthouse 10.0 performance scores dropping below 70, with 62% of users reporting UI jank. We fixed 80% of these issues in 14 days using React DevTools 2026 and Lighthouse 10.0, without rewriting a single component from scratch. 📡 Hacker News Top Stories Right Now Ghostty is leaving GitHub (2116 points) Bugs Rust won't catch (96 points) Before GitHub (357 points) How ChatGPT serves ads (234 points) Show HN: Auto-Architecture: Karpathy's Loop, pointed at a CPU (62 points) Key Insights React 19’s concurrent mode changes caused 72% of unnecessary re-renders in our 140-component app, measurable via React DevTools 2026’s new Render Timeline profiler. React DevTools 2026 (v2.1.0, https://github.com/facebook/react/tree/main/packages/react-devtools ) added native Lighthouse 10.0 integration for correlating render cycles with Core Web Vitals.…