CSS Overscroll Behavior in Chrome
Blink28621 Marras 2025

CSS Overscroll Behavior in Chrome

The source provides a comprehensive technical guide to the CSS overscroll-behavior properties, which allow web developers to control scroll chaining and boundary effects like pull-to-refresh or elastic rubber-banding. It details the three main values—auto, contain, and none—explaining how they affect both nested scrolling elements and the root viewport, distinguishing between stopping scroll propagation and suppressing visual overscroll feedback. A significant portion of the text is dedicated to explaining Chrome's implementation pipeline, outlining how the CSS properties are parsed by the Blink rendering engine, propagated to the compositor thread (the cc component) for efficient scroll handling, and finally interpreted by platform-specific code on Android and macOS to control native UI features. The text emphasizes that using this CSS property is the recommended, high-performance method for managing complex scrolling interactions in modern web applications and embedded content.

Jaksot(397)

Blink Implementation of View Transition Layer Participation

Blink Implementation of View Transition Layer Participation

The provided text explains how the Blink rendering engine manages elements during a View Transition API lifecycle. It details the criteria for participation, where elements must be assigned a unique v...

4 Helmi 27min

Correcting Chained Anchor Fallback Selection in Blink

Correcting Chained Anchor Fallback Selection in Blink

The provided text describes a technical patch for the Blink rendering engine designed to fix how CSS anchor positioning handles complex "chained" scenarios. Specifically, it addresses a bug where anch...

3 Helmi 28min

Hit Testing Architecture in Blink and Chromium

Hit Testing Architecture in Blink and Chromium

This document explores the technical architecture of hit testing within the Chromium and Blink engines, the process used to link user input to specific interface elements. The system operates across m...

2 Helmi 31min

Collaborative Intelligence: Multi-Agent LLM Systems for Software Engineering

Collaborative Intelligence: Multi-Agent LLM Systems for Software Engineering

Recent research highlights the shift from single AI models to multi-agent systems that use specialized roles to conquer complex programming challenges. These frameworks, such as Microsoft’s AutoGen an...

1 Helmi 52min

A Decade Diverged: WebKit Evolution After the Blink Fork

A Decade Diverged: WebKit Evolution After the Blink Fork

This technical report chronicles the divergent evolution of the WebKit and Blink engines following their 2013 split, focusing on their distinct design philosophies and architectural paths. While both ...

31 Tammi 38min

Mastering CSS Scroll-Triggered and Scroll-Driven Animations

Mastering CSS Scroll-Triggered and Scroll-Driven Animations

Modern CSS has introduced scroll-triggered animations, a new feature that allows developers to initiate time-based effects when a user reaches specific scroll thresholds. Unlike scroll-driven animatio...

31 Tammi 34min

Chromium Compositor Implementation of CSS Sticky Positioning

Chromium Compositor Implementation of CSS Sticky Positioning

In Chromium, sticky positioning is managed by the compositor thread to ensure smooth scrolling without relying on the main layout engine. The process begins on the main thread, where layout constraint...

31 Tammi 31min

Modern Web Scrolling: Mechanics of Driven and Triggered Animations

Modern Web Scrolling: Mechanics of Driven and Triggered Animations

Modern web standards are evolving to support scroll-driven animations, which tie the progress of visual effects directly to a user’s scroll position rather than a standard clock. Traditionally, these ...

31 Tammi 31min