History of PushSubscription.toJSON() Revision history for: English (US) Mar 17, 2016, 2:28:54 PM chrisdavidmills Previous Jan 22, 2016, 2:27:19 PM kitcambridge The serializer was added in Firefox 46. Previous Jan 18, 2016, 12:48:52 AM chrisdavidmills Previous Dec 8, 2015, 12:57:00 PM chrisdavidmills Nov 2, 2015, 6:55:56 AM chrisdavidmills