Dragging HeaderView works even when the mouse event is accepted by a MouseArea inside an (header) cell

When implementing the delegate for HorizontalHeaderView and using a MouseArea to fill the delegate for managing the mouse events, sometimes the Drag&Drop of the column will be activated even when the event is accepted by the MouseArea.

Reproduce:

1. Set the mouse.accepted = false, for example when using the Alt modifier
2. Try to drag the column and drop it to another place (using Alt modifier).
3. Set the mouse.accepted = true, for example when the Alt modifier is not pressed.
4. Try to drag the column and drop it to another place (using no modifiers).

Expected:

The Drag&Drop for the column should not work as the mouse is accepted

Observed:

The column is able to be moved to another place.

Snippet:

HorizontalHeaderView {
    syncView: tableView
    movableColumns: true
    delegate: Rectangle {
        Label {
            anchors.centerIn: parent
            text: model.columnName
        }
        MouseArea {
            anchors.fill: parent
            onPressed: function(event) {
                if (event.modifiers === Qt.AltModifier) {
                    event.accepted = false
                    return
                }
            }
        }
    }
}