Google reduced Chrome for Android scroll jank by 48%

Key Points:

• Google has reduced scroll jank in Chrome for Android by 48% between 2023 and 2026, improving the smoothness of page scrolling and addressing sudden stutters caused by delayed frame updates.
• Scroll jank occurs when Chrome misses the strict frame delivery deadline, causing the screen to display outdated scroll positions and resulting in jerky visual stutters perceived by users.
• Chrome’s multi-process architecture, involving browser, renderer, and GPU processes, complicates scroll event handling and contributes to scroll jank, as input events and frame updates traverse different threads and processes.
• To combat this, Google implemented input prediction to generate synthetic scroll updates when input events are delayed, and re-architected browser controls rendering to allow the GPU process to handle scroll offsets independently, reducing visual hiccups.
• These improvements stem from a combination of automated heuristics, targeted optimizations, and deep architectural changes aimed at delivering a more consistent and fluid mobile web experience.