Ability to load images into the frame buffer

V-ray has a feature where you can load an image into the frame buffer, then you can region-render or render selected over the image.

I used this a lot when I used V-ray, really handy if you want to add a small element to the scene or change a colour of something to a previously rendered scene.

Much easier than region-rendering then photoshopping the region to the old image.

Valid feature request, already requested many times, we will look for duplicates and provide some info if/when we can expect it.

Closing as duplicate of: https://forum.corona-renderer.com/ Loading Corona EXR into VFB