The source provides an extensive technical overview of how the Blink rendering engine handles scrolling, particularly focusing on the main-thread scrolling lifecycle. It explains that while modern browsers prioritize fast, asynchronous compositor-thread scrolling, the main thread is required for complex scenarios involving features like fixed backgrounds, non-passive event listeners, or layout updates on scroll. The document details the core architecture, including DOM APIs like scrollTo(), internal classes like ScrollableArea and LocalFrameView, and the interaction between scrolling and the style, layout, and paint phases of the rendering pipeline, noting that main-thread scrolls often skip layout but require paint invalidation for affected elements such as position:sticky. Finally, it covers how Blink manages scroll events, scroll anchoring, and synchronizes the final scroll position with the compositor for display.