SUMMARY When we want to restore the default background of a SDDM theme using the new SDDM KCM, we need to set another SDDM theme and then switch back to the initial one. "Clear image" button just sets a blue background to SDDM. A clearer way to restore the default background would be nice. SOFTWARE/OS VERSIONS Operating System: KDE neon Unstable Edition KDE Plasma Version: 5.21.80 KDE Frameworks Version: 5.79.0 Qt Version: 5.15.2
Yeah this mildly annoys me too.
On Plasma 6 it's impossible to restore the SDDM background even applying a non-Breeze SDDM theme and then switching back to the Breeze one. Also "Defaults" button in the KCM and "Clear image" button in the "Change background" popup do not work. Operating System: KDE neon Unstable Edition KDE Plasma Version: 5.27.80 KDE Frameworks Version: 5.240.0 Qt Version: 6.6.0 Graphics Platform: Wayland
As I understand it, clearing the image falls back to the color setting in the config file. This looks like an Easter egg, as there is no UI setting for it.