SyncEvent

Limited availability

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

See full compatibility

Note: This feature is only available in Service Workers.

The SyncEvent interface of the Background Synchronization API represents a sync action that is dispatched on the ServiceWorkerGlobalScope of a ServiceWorker.

This interface inherits from the ExtendableEvent interface.

Constructor

SyncEvent(): Creates a new SyncEvent object.

Instance properties

Inherits properties from its parent, ExtendableEvent and Event.

SyncEvent.tag Read only: Returns the developer-defined identifier for this SyncEvent.
SyncEvent.lastChance Read only: Returns true if the user agent will not make further synchronization attempts after the current attempt.

Instance methods

Inherits methods from its parent, ExtendableEvent and Event.

None.

Specifications

Specification
Web Background Synchronization # sync-event

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
`SyncEvent`	Chrome – Full support Chrome 49 (Release date: 2016-03-02) footnote Full support	Edge – Full support Edge 79 (Release date: 2020-01-15) footnote Full support	Firefox – No support Firefox footnote No support	Opera – Full support Opera 36 (Release date: 2016-03-15) footnote Full support	Safari – No support Safari footnote footnote See bug 182565	Chrome Android – Full support Chrome Android 49 (Release date: 2016-03-09) footnote Full support	Firefox for Android – No support Firefox for Android footnote No support	Opera Android – Full support Opera Android 36 (Release date: 2016-03-31) footnote Full support	Safari on iOS – No support Safari on iOS footnote footnote See bug 182565	Samsung Internet – Full support Samsung Internet 5 (Release date: 2016-12-15) footnote Full support	WebView Android – No support WebView Android footnote footnote See bug 40449796	WebView on iOS – No support WebView on iOS footnote footnote See bug 182565
`SyncEvent()` constructor	Chrome – Full support Chrome 49 (Release date: 2016-03-02) footnote Full support	Edge – Full support Edge 79 (Release date: 2020-01-15) footnote Full support	Firefox – No support Firefox footnote No support	Opera – Full support Opera 36 (Release date: 2016-03-15) footnote Full support	Safari – No support Safari footnote No support	Chrome Android – Full support Chrome Android 49 (Release date: 2016-03-09) footnote Full support	Firefox for Android – No support Firefox for Android footnote No support	Opera Android – Full support Opera Android 36 (Release date: 2016-03-31) footnote Full support	Safari on iOS – No support Safari on iOS footnote No support	Samsung Internet – Full support Samsung Internet 5 (Release date: 2016-12-15) footnote Full support	WebView Android – No support WebView Android footnote footnote See bug 40449796	WebView on iOS – No support WebView on iOS footnote No support
`lastChance`	Chrome – Full support Chrome 49 (Release date: 2016-03-02) footnote Full support	Edge – Full support Edge 79 (Release date: 2020-01-15) footnote Full support	Firefox – No support Firefox footnote No support	Opera – Full support Opera 36 (Release date: 2016-03-15) footnote Full support	Safari – No support Safari footnote No support	Chrome Android – Full support Chrome Android 49 (Release date: 2016-03-09) footnote Full support	Firefox for Android – No support Firefox for Android footnote No support	Opera Android – Full support Opera Android 36 (Release date: 2016-03-31) footnote Full support	Safari on iOS – No support Safari on iOS footnote No support	Samsung Internet – Full support Samsung Internet 5 (Release date: 2016-12-15) footnote Full support	WebView Android – No support WebView Android footnote footnote See bug 40449796	WebView on iOS – No support WebView on iOS footnote No support
`tag`	Chrome – Full support Chrome 49 (Release date: 2016-03-02) footnote Full support	Edge – Full support Edge 79 (Release date: 2020-01-15) footnote Full support	Firefox – No support Firefox footnote No support	Opera – Full support Opera 36 (Release date: 2016-03-15) footnote Full support	Safari – No support Safari footnote No support	Chrome Android – Full support Chrome Android 49 (Release date: 2016-03-09) footnote Full support	Firefox for Android – No support Firefox for Android footnote No support	Opera Android – Full support Opera Android 36 (Release date: 2016-03-31) footnote Full support	Safari on iOS – No support Safari on iOS footnote No support	Samsung Internet – Full support Samsung Internet 5 (Release date: 2016-12-15) footnote Full support	WebView Android – No support WebView Android footnote footnote See bug 40449796	WebView on iOS – No support WebView on iOS footnote No support

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Full support: Full support
No support: No support
: See implementation notes.

This page was last modified on Apr 19, 2024 by MDN contributors.

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