Thank God! I believe I might have had the old Space Fantasy, but when Firefox updated a while back the Theme was completly gone and firefox was plain black! I've searched forever to find this again!

The only thing I'd wish for is to get rid of the slight transparent gray background behind the URL/Search bar and Bookmarks. I've seen other themes without it, so it must be possible, but I have no clue how to even make my own themes, let alone editing existing ones