file:///home/qydw/kde/usr/lib64/qml/org/kde/plasma/components/MenuItem.qml:18:5: Unable to assign QPalette to QQuickPalette*
Same should go for Menu, I guess. It's a long story, but the end result is that QPalette as exposed by Kirigami is not compatible with QQuickPalette which QQC2 and QtQuick expects to see.
By the way: https://invent.kde.org/frameworks/kirigami/-/merge_requests/1237