When it comes to browser-themes 'Blue Space Abstract' is on the darker-side, yet it isn't an overly dark theme. My favorite thing about it, is that its unique to F.F. (obviously since it has the F.F. logo), which is refreshing for someone who is tired of the same themes that are cross browser, and seemingly are installed on nearly every browser. Further more, the Graphic designer who designed the Mozilla logo in this theme is obviously a top notch artist. Good Job on this theme FF user 12487170!!!