PointerEvent.getCoalescedEvents() - Web APIs
safari no support nowebview android full support 58chrome android full support 58firefox android partial support 59disabled partial support 59disabled disabled from version 59: this feature is behind the dom.w3c_pointer_events.enabled preference (needs to be set to true).

PointerEvent.isPrimary - Web APIs
if there are multiple primary pointers, these pointers will all produce compatibility mouse events (see pointer_events for more information about pointer, mouse and touch interaction).