indow.requestIdleCallback() method queues a function to be called during a browser's idle periods. This enables developers to perform background and low priority work on the main event loop, without impacting latency-critical events such as animation and input response. Functions are generally called in first-in-first-out order unless the function's timeout is reached before the browser calls it.
var handle = window.requestIdleCallback(callback[, options])
An unsigned long integer that can be used to cancel the callback using the
- A reference to a function that should be called in the near future. The callback function takes a deadline argument with the following properties:
timeRemaining: A reference to a method that returns a
didTimeout: A boolean that returns false if the callback was invoked by the user agent during idle, and true otherwise (e.g. if a timeout option was given and expired before there was sufficient idle time).
- Contains optional configuration parameters. It has the following property:
timeout: The minimum time that must pass before calling the callback function. This value is given in milliseconds.
|Cooperative Scheduling of Background Tasks||Working Draft||Initial definition.|
|Feature||Chrome||Firefox (Gecko)||Internet Explorer||Opera||Safari (WebKit)|
|Basic support||47||No support||No support||34||No support|
|Feature||Android||Android Webview||Firefox Mobile (Gecko)||Firefox OS||IE Mobile||Opera Mobile||Safari Mobile||Chrome for Android|
|Basic support||No support||47||?||?||?||?||?||47|
 On track for release in Firefox 52, see bug 1198381.