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IdleDetector: start() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Note: This feature is available in Dedicated Web Workers.

The start() method of the IdleDetector interface returns a Promise that resolves when the detector starts listening for changes in the user's idle state. This method takes an optional options object with the threshold in milliseconds where inactivity should be reported and signal for an AbortSignal to abort the idle detector.

Syntax

start()
start(options)

Parameters

options Optional

An object with the following properties:

threshold

The minimum number of idle milliseconds before reporting should begin.

signal

A reference to an AbortSignal instance allowing you to abort idle detection.

Return value

A Promise.

Exceptions

NotAllowedError DOMException

Use of this feature was blocked by a Permissions Policy.

Examples

The following example shows how to start idle detection using the options argument. It retrieves an instance of AbortSignal from an instance of AbortController.

const controller = new AbortController();
const signal = controller.signal;

await idleDetector.start({
  threshold: 60_000,
  signal,
});
console.log("IdleDetector is active.");

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS
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https://developer.mozilla.org/en-US/docs/Web/API/IdleDetector/start