[Feature Request] Full SSR support

[AndrewBogdanovTSS]

Right now the only proper way of using this lib with SSR is to wrap it in tag. But is it possible to implement a full SSR support so images would also properly render to SSR? The issue that exists right now is that if is omitted sometimes intersection observer is not triggered after initial load and images appear hidden although they are already within a viewport

[alexjoverm]

Do you think it would be fixed by #78? Or there would be other things take into consideration?