KDE Frameworks 5.55.0
Qt 5.9.7 (built against 5.9.7)
The xcb windowing system
kernel 4.12.14-lp151.28.48-default #1 SMP Fri Apr 17 05:38:36 UTC 2020 (18849d1) x86_64 x86_64 x86_64 GNU/Linux
OS : opensuse leap 15.1

I got an error when starting this command from command line :

Code: Select all

kcmshell5 kcm_desktoptheme
org.kde.kcoreaddons: Error loading plugin "kcm_desktoptheme" "The shared library was not found."
Plugin search paths are ("/usr/lib64/qt5/plugins", "/usr/bin")
The environment variable QT_PLUGIN_PATH might be not correctly set
file:///usr/lib64/qt5/qml/org/kde/kirigami.2/private/globaltoolbar/BreadcrumbControl.qml:63:59: Unable to assign QQuickItem to Page_QMLTYPE_40
file:///usr/lib64/qt5/qml/org/kde/kirigami.2/templates/AbstractApplicationHeader.qml:46:25: Unable to assign QQuickItem to Page_QMLTYPE_40
qt.svg: link XMLID_5_ hasn't been detected!

Effectively the plugin "kcm_desktoptheme" does not exists.
But the desktop "theme editor - System settings module" nevertheless open itself.

Same kind of error with :

Code: Select all

kcmshell5 kcm_lookandfeel
org.kde.kcoreaddons: Error loading plugin "kcm_lookandfeel" "The shared library was not found."
Plugin search paths are ("/usr/lib64/qt5/plugins", "/usr/bin")
The environment variable QT_PLUGIN_PATH might be not correctly set
file:///usr/lib64/qt5/qml/org/kde/kirigami.2/private/globaltoolbar/BreadcrumbControl.qml:63:59: Unable to assign QQuickItem to Page_QMLTYPE_41
file:///usr/lib64/qt5/qml/org/kde/kirigami.2/templates/AbstractApplicationHeader.qml:46:25: Unable to assign QQuickItem to Page_QMLTYPE_41


Any comment is welcome.

Did you check if you have everything installed correctly?