What makes you think it's abandoned? The author is active on Twitter, the last update for dark mode was in May 2019 and I don't see any show stopper bugs or crashes on Catalina. Small utilities like this don't need an update every month. I bought it a while ago because
1) It's very cheap and a great show case for a small niche Mac app that's both beautiful and works well
2) The two times per year I use it, it's already worth it and fun to play around with.
https://blog.helftone.com
