Note: This feature is only available in Service Workers.
The ExtendableEvent() constructor creates a new ExtendableEvent object.
new ExtendableEvent(type)
new ExtendableEvent(type, options)typeA string with the name of the event. It is case-sensitive.
options OptionalAn object that, in addition of the properties defined in Event(), can contain any custom settings that you want to apply to the event object. Currently no possible options are mandatory, but this has been defined for forward compatibility across the different derived events.
A new ExtendableEvent object.