I notice that Ctrl-Click in the HSL Equalizer has no effect. It is Dariusz Duma’s build of 1.0 on Ubuntu 18.04, in case that matters. While I’m at it - I think that equalizer would be better if it started with fewer pre-set colors in it. They are a hassle to remove, and adding them is trivial.
Finally, the name ART. It is great, like the software, but it sadly doesn’t work well with search engines. I see people typing “download art” into a search engine and getting nowhere.