'DOMSubtreeModified' mutation event is deprecated (in assets.js)

[Algorush]

There is a warning message in Dev Tools: [Deprecation] Listener added for a 'DOMSubtreeModified' mutation event. This event type is deprecated, and will be removed from this browser VERY soon. Usage of this event listener will cause performance issues today, and represents a large risk of imminent site breakage. Consider using MutationObserver instead. See https://chromestatus.com/feature/5083947249172480 for more information. DOMSubtreeModified is using here: https://github.com/3DStreet/3dstreet/blob/afec8fd93a8bf54549ce809a1d06fd131a8ff1fd/src/assets.js#L345