How we built it

Intersection Observer

The Intersection Observer API can be used to asynchronously observe changes in the intersection of a target Element with an ancestor element (for infinite scrolling lists) or the top-level document's viewport (for 'viewability' tracking).

Documentation

Specification

Working draft or equivalent

Status in Chromium

Enabled by default (launch bug) in:

  • Chrome for desktop release 51
  • Chrome for Android release 51
  • Android WebView release 51
  • Opera release 38
  • Opera for Android release 38

Consensus & Standardization

Owners

Last updated on 2016-09-02