I don´t know whether this will lead anywhwere but I´d like to tell you about an app which might be of help in the matter
Looking a bit around in the web I stumbled upon the page https://www.ubuntupit.com/best-linux-wallpaper-changer/ .
Of all the wallpaper changers presented there was wallpapoz which caught my eye:
In the description it says:
it has one unique feature. It can set up different wallpapers for different workspaces. For this reason, when you switch your workspaces, you will get a different ambiance.
Looking it up on Wallpapoz › Archiv › Wiki › ubuntuusers.de I found out that …
Wallpapoz was originally developed for the GNOME 2 desktop environment and consists of two components […]
The latest version is said to support GNOME 3 and Xfce. Yet there was no mention of LXQt.
So I don´t know whether the programm would work with Lubuntu 20.04.
The program requires a dependency package, which is not installed automatically.
So you have to install it before the actual installation of Wallpapoz
(translated from German)
sudo apt-get install python-imaging
Yet it seems there´s no installation candidate for that one.
Does anybody know a bit more about wallpapoz (https://vajrasky.wordpress.com/ ) and how to install it?
Or if it works with LXQt at all?
Thanks a lot in advance.