How we built it

Support "once" event listener option

Support adding event listeners with the "once" option set to true. When set to true, options’s once member indicates that the callback will only be invoked once after which the event listener will be removed.

Comments

It is already supported in Safari Technology Preview 7, vaguely mentioned in https://webkit.org/blog/6640/release-notes-for-safari-technology-preview-release-7/

Documentation

Specification

Established standard

Status in Chromium

Enabled by default (launch bug) in:

  • Chrome for desktop release 55
  • Chrome for Android release 55
  • Android WebView release 55
  • Opera release 42
  • Opera for Android release 42

Consensus & Standardization

Owner

Last updated on 2016-12-01