I am running Lubuntu 18.04 on my old laptop. It works great even thought the hardware is almost 8 years old.
I recently installed Fondo, the desktop background changing app, from Flathub. The link is- Fondo on Flatpak
I can start the program. Usually, Fondo shows you a bunch of wallpapers to choose from, and you just select one of them to be your desktop background. But when I click on a wallpaper, nothing happens. In have tried it multiple times, without any success. Someone please help me with this.
I also run Linux Mint 19 on other laptop. I installed Fondo from Flathub there as well. But it works very smoothly on Mint 19.