UIEvent - Web APIs | MDN
Returns a long with details about the event, depending on the event type. Returns the horizontal coordinate of the event relative to the current layer. Returns the vertical coordinate of the event relative to the current layer. UIEvent.sourceCapabilities Read only Returns an instance of the InputDeviceCapabilities interface, which provides information about the physical device responsible for generating a touch event.
https://developer.mozilla.org/en-US/docs/Web/API/UIEvent