Created attachment 168779 [details] Stack trace SUMMARY It crashed, if the specified theme is not present/accessible (?). The only working Theme is "Fusion". This is happened on hyprland, as I was testing polkit with it. Nonetheless, it should not crash. STEPS TO REPRODUCE 1. Run "QT_STYLE_OVERRIDE=Adwaita-Dark /usr/libexec/kf6/polkit-kde-authentication-agent-1" 2. Open a program that requests elevated rights (rg. partitionmanager) OBSERVED RESULT Crash. Some stdout output: > QQmlApplicationEngine failed to load component > qrc:/qml/QuickAuthDialog.qml: module "Adwaita-Dark" is not installed > KCrash: appFilePath points to nullptr! > KCrash: Application '<unknown>' crashing... crashRecursionCounter = 2 > Segmentation fault EXPECTED RESULT No crash and a themed dialog that elevated rights. SOFTWARE/OS VERSIONS CAUTION: I was using hyprland! Linux: Nobara Linux 39 KDE Plasma Version: 6.0.3 KDE Frameworks Version: 6.0.0 Qt Version: 6.6.2 ADDITIONAL INFORMATION If you enter something random as QT_STYLE_OVERRIDE, it does not crash. It instead tells you which styles could be used and falls back to Fusion. > Available styles: Breeze, qt5ct-style, qt6ct-style, HighContrastInverse, HighContrast, Adwaita-HighContrastInverse, Adwaita-HighContrast, Adwaita-Dark, Adwaita, Windows, Fusion