Slider, handle and mouse cursor

[SteveMS]

Hi.
I created a simple default Qt Quick project.

ApplicationWindow {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")

    menuBar: MenuBar {
        Menu {
            title: qsTr("File")
            MenuItem {
                text: qsTr("&Open")
                onTriggered: console.log("Open action triggered");
            }
            MenuItem {
                text: qsTr("Exit")
                onTriggered: Qt.quit();
            }
        }
    }

    MySlider{
        id: myslider
    }

}

With MySlider.qml :

Item {
    id: itemSlider
    x: 0
    y: 0
    width: 200
    height: 300

    Rectangle {
        id: background
        width: 200
        height: 300
        color:Qt.rgba(0.2,0.2,0.2,1);
    }

    Slider {
        id:slider
        orientation: Qt.Vertical
        width: 200
        height: 300
        anchors.horizontalCenter: parent.horizontalCenter
        anchors.verticalCenter: parent.verticalCenter

        style: SliderStyle {
            groove: Rectangle {
                width: 300
                height: 2
                color: Qt.rgba(1,0,0,1);
            }
            handle: Rectangle {
                anchors.centerIn: parent
                color: Qt.rgba(0.7,0.7,0.7,1);
                width: 10
                height: 10
            }
        }
    }

}

If I put the next values for the handle

width: 10
height: 10

then, when I move the handle it stays Under the mouse cursor.
However if I put the next values to have a flattened handle

width: 10
height: 100 //the greater the value is, the greater the offset between the handle and the mouse cursor is

then the handle doesn't follow the mouse cursor, there is an offset between the two.

What is the problem? Is it a bug?
Thanks.

[SteveMS]

Apparently, it seems to be a bug so I reported it on Qt bugreports.
https://bugreports.qt.io/browse/QTBUG-51953