Potol 6 LXQt
I thought I had it back but the last upgrade wiped it again and I erased my older timeshifts.
I noticed the LXQt in Manjaro has no openbox right click on the desktop either.
I am not in Sparky6 - Testing. Just a thought, I am in stable. maybe LXQT in your one case is running xfwm4 instead of openbox. LXQT is supposed to be able to use either of them. There is toggle to select in preferences somewhere. But it could very well be something else. Best of luck.
Herein lies the problem
Preferences
LXQT settings
Session settings
Basic settings
LXQT modules.
Uncheck the desktop...leave the rest...all your panels and stuff remain intact and you get your full right click openbox menu right click back wherever you click on the desktop
Glitch: any desktop/wallpaper you want to use goes in opt/artwork for nitrogen to properly use without secretly enabling the damn desktop in LX.