diff --git a/src/kconfigdialogmanager.cpp b/src/kconfigdialogmanager.cpp
--- a/src/kconfigdialogmanager.cpp
+++ b/src/kconfigdialogmanager.cpp
@@ -592,7 +592,27 @@
 
 void KConfigDialogManagerPrivate::onWidgetModified()
 {
-    const auto widget = qobject_cast<QWidget*>(q->sender());
+    const auto senderWidget = qobject_cast<QWidget *>(q->sender());
+    Q_ASSERT(senderWidget);
+    const auto widget = [=]() -> QWidget * {
+        const auto senderButton = qobject_cast<QAbstractButton *>(senderWidget);
+        if (!senderButton) {
+            return senderWidget;
+        }
+
+        if (senderButton->objectName().startsWith("kcfg_")) {
+            return senderButton;
+        }
+
+        for (auto groupBox : qAsConst(allExclusiveGroupBoxes)) {
+            const auto buttons = groupBox->findChildren<QAbstractButton *>();
+            if (buttons.contains(senderButton)) {
+                return groupBox;
+            }
+        }
+
+        return senderButton;
+    }();
     Q_ASSERT(widget && widget->objectName().startsWith("kcfg_"));
     const auto configId = widget->objectName().mid(5);
     updateWidgetIndicator(configId, widget);