Andrew Cox enhanced UI reliability in the facebook/litho repository by refactoring horizontal scroll pre-draw handling. He replaced deprecated pre-draw logic in HorizontalScrollComponentSpec with the OneShotPreDrawListener, streamlining the rendering path for horizontal scrolling components. This technical approach, implemented using Java and Kotlin, reduced pre-draw stalls and mitigated the risk of application not responding (ANR) events in scroll-heavy Android user interfaces. Andrew’s work focused on performance optimization and maintainability, encapsulating the changes in a targeted cleanup and experiment commit. The update improved code cleanliness and aligned with broader efforts to ensure smoother, more responsive UI experiences in Android development.