TextMetrics width is not same as Text.implicitWidth

 Text {
        id: txt
        text: qsTr("NOT FOR PATIENT USE")
        height: 14
        font.pixelSize: 11
        font.family: "Courier" // "Arial"
        color: "#2B2D2E"
        font.letterSpacing: 0
    }
    TextMetrics {
        id: textMetrics
        font: txt.font
        text: txt.text
    }
    Component.onCompleted: {
        console.log("textMetrics.width: ",textMetrics.width )
        console.log("txt.implicitWidth: ",txt.implicitWidth )
    }

For "Arial" font:
qml: textMetrics.width: 109
qml: txt.implicitWidth: 125

For "Courier" font:
qml: textMetrics.width: 151
qml: txt.implicitWidth: 152