Passive Event Listeners is a way to improve the scroll performance by unblocking scrolling on touch and wheel event listeners, so that scrolling happens immediately while the events are processed by javascript. alexclarke@ proposed that we should treat all the touchstart and first touchmove event listeners as passive while there’s an active fling animation.

Demo

Documentation

Specification

Editor's draft

Status in Chromium

Blink


Browser Intervention (tracking bug) in:

  • Chrome for desktop release 57
  • Chrome for Android release 57

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.

  • Shipped/Shipping
  • Shipped/Shipping
  • No signal
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Owners

Comments

Safari sets events’ cancelable to be false while the fling animation is active, and calling ‘preventDefault’ does not have any effect on them. Our intervention has the same behaviors, but we see non-cancelable events more often, maybe because our configured fling speed is lower or fling interval is longer. Firefox and IE/Edge do not handle the event listeners at all during fling.

Search tags

Passive Listeners, Touch Intervention, intervention,

Last updated on 2020-11-09