I'm having a couple of very different components and often I need to do some work on the components root DOM-node. Some of the compos have Version<=39.0 other have 40.0+ and therefore I'm not looking for anything which is relaying on Locker Service Secure Window.
I know already it works fine like this
var rootElement = component.find("thisIsTheRoot").getElement();
This would help me, because I'm writing JS residing in a static resource which should work across all of my components regardless of any markup-wrapper.