This feature is not Baseline because it does not work in some of the most widely-used browsers.
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.
SyncEvent()Creates a new SyncEvent object.
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.
Inherits methods from its parent, ExtendableEvent and Event.
None.
| Specification |
|---|
| Web Background Synchronization> # sync-event> |
| 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 |
49 | 79 | No | 36 | No | 49 | No | 36 | No | 5.0 | No | No |
SyncEvent |
49 | 79 | No | 36 | No | 49 | No | 36 | No | 5.0 | No | No |
lastChance |
49 | 79 | No | 36 | No | 49 | No | 36 | No | 5.0 | No | No |
tag |
49 | 79 | No | 36 | No | 49 | No | 36 | No | 5.0 | No | No |
© 2005–2025 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/SyncEvent