Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The SyncEvent() constructor creates a new SyncEvent object.


var mySyncEvent = new SyncEvent(type, init)



The type of the Event.

init Optional

An options object containing any custom settings that you want to apply to the event object. Options are as follows:

  • tag: A developer-defined unique identifier for this SyncEvent.
  • lastChance: A boolean value indicating that the user agent will not make further synchronization attempts after the current attempt.

Browser compatibility

BCD tables only load in the browser