An alternative fix would be adding a plasma desktop theme and setting
the default background there. That alternative doesn't require a custom
script for setting the background image.
For example:
(using /usr/share/plasma/desktoptheme/default/metadata.desktop as a
template)
$ cat /usr/share/plasma/desktoptheme/debian-theme/metadata.desktop
[Desktop Entry]
Name=DebianTheme
Comment=[...]
X-KDE-PluginInfo-Author=[...]
X-KDE-PluginInfo-Email=[...]
X-KDE-PluginInfo-Name=Debian Theme
X-KDE-PluginInfo-Version=1.0
X-KDE-PluginInfo-Website=[...]
X-KDE-PluginInfo-Category=
X-KDE-PluginInfo-Depends=
X-KDE-PluginInfo-License=[...]
X-KDE-PluginInfo-EnabledByDefault=true
X-Plasma-API=5.0
[Settings]
FallbackTheme=default
[Wallpaper]
defaultWallpaperTheme=DebianTheme
defaultFileSuffix=.png
defaultWidth=1920
defaultHeight=1080
-------
And configure that theme as default:
$ cat /etc/xdg/plasmarc
[Theme]
name=DebianTheme
--
Daniel Ruiz de Alegría
drasite.com