If you open any Kirigami app (Kirigami Gallery, Discover) and tab your way through the UI, at least the toolbuttons on the tool bar won't show a decoration. It works on widgets applications with breeze. It works if I set QT_QUICK_CONTROLS_STYLE=org.kde.breeze. It doesn't work if I change the QStyle to a different one.
A possibly relevant merge request was started @ https://invent.kde.org/frameworks/qqc2-desktop-style/-/merge_requests/412
Git commit c6006ca5d16e6374a3c5a03da380f03e590442c4 by Aleix Pol. Committed on 26/05/2024 at 00:58. Pushed by apol into branch 'master'. Fix rendering the focus of our items Due to a Qt bug, we cannot rely on QQuickControl::focusReasonChanged to notify us when our focus reason changes. https://bugreports.qt.io/browse/QTBUG-125725 Instead, check which is the focus reason changes. I suggest we ifdef it out once we find a good fix. M +2 -0 plugin/kquickstyleitem.cpp https://invent.kde.org/frameworks/qqc2-desktop-style/-/commit/c6006ca5d16e6374a3c5a03da380f03e590442c4