This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
() method on the
IdleDeadline interface returns the estimated number of milliseconds remaining in the current idle period. The callback can call this method at any time to determine how much time it can continue to work before it must return. For example, if the callback finishes a task and has another one to begin, it can call
timeRemaining() to see if there's enough time to complete the next task. If there isn't, the callback can just return immediately, or look for other work to do with the remaining time.
By the time
timeRemaining() reaches 0, the callback must return control to the user agent's event loop.
timeRemaining = IdleDeadline.timeRemaining();
DOMHighResTimeStamp value (which is a floating-point number) representing the number of milliseconds the user agent estimates are left in the current idle period. The value is ideally accurate to within about 5 microseconds.
|Cooperative Scheduling of Background Tasks||Working Draft|
|Feature||Chrome||Edge||Firefox (Gecko)||Internet Explorer||Opera||Safari (WebKit)|
|Basic support||47||No support||53 (53)||No support||34||No support|
|Feature||Android||Chrome||Firefox Mobile (Gecko)||Firefox OS||IE Phone||Opera Mobile||Safari Mobile|
|Basic support||53||55||53.0 (53)||?||No support||37||No support|
 Idle callback support was added in Firefox 53, but was disabled by default. To enable it, set the preference
true. Idle callbacks are enabled by default starting in Firefox 55.
- Collaborative Scheduling of Background Tasks