Microsoft is overhauling Windows 11 through the Windows K2 initiative, transitioning core UI elements from third-party frameworks to the native WinUI 3. Engineer Beth Pan confirmed these improvements via GitHub, with File Explorer and Notepad serving as benchmarks for the responsiveness overhaul. This fundamental shift aims to eliminate the performance bottlenecks that have plagued Windows 11 since its launch.

The latest WinUI 3 patches deliver substantial gains: 41% fewer allocations, 63% fewer transient allocations, 45% fewer function calls, and 25% less time spent in the WinUI framework. These optimizations will make File Explorer launch nearly instant by reducing background processing time. The improvements are expected to arrive with the next set of Windows updates as Microsoft integrates the changes into WinAppSDK 2.x.

Currently, Windows 11 mixes legacy frameworks including WebView2 and React with modern components, creating inconsistent interfaces carried over from Windows 7. Microsoft's complete transition to WinUI 3 will reduce application latency and create a smoother experience. The Low Latency Profile feature further enhances performance by boosting CPU frequency to maximum for 1-3 seconds during application launches, ensuring a responsive user experience.