delete unknown json objects + write missing objects to config file

Components/Menu.qml

@@ -126,7 +126,7 @@ MouseArea {
 					CustomRect {
 						id: item
 
-						readonly property bool active: modelData === root.active
+						readonly property bool active: modelData === root?.active
 						required property int index
 						required property MenuItem modelData
 
@@ -163,19 +163,19 @@ MouseArea {
 							MaterialIcon {
 								Layout.alignment: Qt.AlignVCenter
 								color: item.active ? Colors.palette.m3onTertiaryContainer : Colors.palette.m3onSurfaceVariant
-								text: item.modelData.icon
+								text: item.modelData?.icon ?? ""
 							}
 
 							CustomText {
 								Layout.alignment: Qt.AlignVCenter
 								Layout.fillWidth: true
 								color: item.active ? Colors.palette.m3onTertiaryContainer : Colors.palette.m3onSurface
-								text: item.modelData.text
+								text: item.modelData?.text ?? ""
 							}
 
 							Loader {
 								Layout.alignment: Qt.AlignVCenter
-								active: item.modelData.trailingIcon.length > 0
+								active: item.modelData?.trailingIcon.length > 0
 								asynchronous: true
 								visible: active