Feature request - Image preload

[tlacaelelrl]

Not sure if this is already possible but I could not fnd it.

Some studies which are large take a long time to load, specialy CTs, is there any way to add a generic image while a particular image within a series has not been loaded but someone navigates to that stack index?

Or on the other hand, is there a way to replace a particular stack index, say pass the generic image as the stack index initially but then replace it with another one?