Clean up scenes preview images when they are no longer needed
The feature to show scenes preview images as part of the storyboard elements is cool. However, updating the images does not get rid of the old ones, cluttering the disk space:
Would be great if the files would either be automatically cleaned up (when updating images, when unloading a library etc.). Alternatively provide an option to clean up the images (scan through all models, determine what images can be deleted, delete them).