Yes. The “Cycle” button at the top of the Working Area on the left lets you step through a variety of different grayscale and color backgrounds. In this way, you can see your work against all kinds of backdrops and see if cropping as well as masks look right on both dark and light desktops.
We've tried to anticipate most questions you might have. However, if you can't find the answer you're looking for here, send us your query and we'll answer it personally.