task-1811: an answer with no words in it, above 16 pt
Windows: download UnluminousSetup-0.37.2-x64.exe below and run it. It installs into
%LOCALAPPDATA%\Programs\Unluminous with no elevation prompt, and puts unluminous and unluminous-cli on the PATH.
Unluminous -> About Unluminous in the window says which build this is.