This feature is not Baseline because it does not work in some of the most widely-used browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Note: This feature is only available in Service Workers.
The tag read-only property of the PeriodicSyncEvent interface returns the developer-defined identifier for the PeriodicSyncEvent. This is specified when calling the PeriodicSyncManager.register() method of the PeriodicSyncManager interface. Multiple tags can be used by the web app to run different periodic tasks at different frequencies.
Returns a String of the defined identifier.
The following example demonstrates listening for a periodic sync event in the service worker, and accessing the tag property.
self.addEventListener("periodicsync", (event) => {
console.log(event.tag); // logs the events tag
});
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
tag |
80 | 80 | No | 67 | No | 80 | No | 57 | No | 13.0 | No | No |
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https://developer.mozilla.org/en-US/docs/Web/API/PeriodicSyncEvent/tag