I'm currently using lxqt with kwin, and since I don't like pcmanfm for my desktop I try setting the wallpaper with nitrogen and it just stays black, this issue has something to do with kwin but i don't know how.
Going to punt this until 1.7 for now - I can't find reasonable documentation on how to set a background for KDE/kwin. This thread from 2015 in particular making me think it's not a thing yet.
I'm currently using lxqt with kwin, and since I don't like pcmanfm for my desktop I try setting the wallpaper with nitrogen and it just stays black, this issue has something to do with kwin but i don't know how.