Row requires Item to have either height or implicitHeight in Qt6 but QUL doesn't

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import QtQuick 2.15
import QtQuick.Templates 2.15
import Thermo 1.0

RadioButton {
    id: control    
    implicitWidth: background.implicitWidth
    implicitHeight: background.implicitHeight
    spacing: 10    
    property alias flag: flagIndicator.source    

    indicator: Image {
        y: control.topPadding + (control.availableHeight - height) / 2
        source: control.checked ? (control.down ? "radiobutton-checked-pressed.png" : "radiobutton-checked.png") : (control.down ? "radiobutton-pressed.png" : "radiobutton.png")
    }    

    background: Item {
        implicitWidth: control.contentItem.implicitWidth
        implicitHeight: Theme.dialogButtonHeight
    }    // Text has no padding properties in UL, so we use Row with an Item for the spacing.

    contentItem: Row {
        anchors.verticalCenter: background.verticalCenter        
        Item {
            implicitWidth: control.indicator.width + control.spacing
        }        
        Image {
            id: flagIndicator
            anchors.verticalCenter: parent.verticalCenter
        }        
        Item {
            implicitWidth: control.spacing
        }        
        Text {
            text: control.text
            color: ColorStyle.greyDark4
            anchors.verticalCenter: parent.verticalCenter
            font.pixelSize: Theme.bottomBarFontSize
        }
    }
}