I read this on your website. However, I can not find anywhere that provides me with a list of keyboard shortcuts for stars, favorites, flags. When I'm in grid view, I can right click over an image but it is greyed out. What does that mean?

"With the grid view and convenient keyboard shortcuts, you can swiftly navigate from one image to another and easily assign stars, colors, favorites, or validation/rejection flags, regardless of the folder where the photos are stored or the software in which they were edited."