defer elements on page load completely or on DOM ready

Hi guys,

I see issues regarding componentDidMount and so on, but I did not found anything anything about the possibility to defer element load not only on presence into viewport, but also after DOM is ready or page is fully loaded.

Is there anything I miss?
Into https://jasonslyvia.github.io/react-lazyload/examples/#/fadein it seems to defer images, but I can't understand how.

It should be very useful for us, since our page has an image on the top part of the screen

Thanks!!