Lightroom: Rendering .PNG files against gray or black background
While Lightroom preserves the alpha channel of .PNG files (great!), it renders thumbnails against a white background. This is good for dark or colored .PNG files, however, it is useless for images that are white or have a lot of light image data (for example, a snow overlay, or white image border overlay). It would be great if Lightroom allowed users to choose to render thumbnails for .PNG files on a 50% gray or black background.