Can I enable a permanent visibility of the background video in the Compositing Pipeline?

Hi,
I made some tests today with the compositing framework. But I am wondering that I see the final result only when I hit play. For creating the light setup of my scene I need a permanent view of the background video or the background image. It is also important to adjust the shadow catcher or shadow receivers. Is this possible? I know the image plate plugin. But this is not the workaround I am looking for.

Best regards, Andreas