[REG 5.11.2 -> 5.12] TextArea's initialization with long text bug

import QtQuick 2.11
import QtQuick.Controls 2.4
import QtQuick.Layouts 1.3
import QtQuick.Window 2.2

ApplicationWindow {
    id: appWindow

    width: 500
    height: 400
    visible: true

    ColumnLayout {
        anchors.fill: parent

        Button {
            text: "Add empty line"
            onClicked: {
                textArea.text += "\n";
            }
        }

        ScrollView {
            Layout.fillWidth: true
            Layout.fillHeight: true

            TextArea {
                id: textArea
                clip: true
                persistentSelection: true
                selectByMouse: true

                font.pointSize: 16
                text: {
                    var s = "";
                    for (var i = 1; i < 30; ++i) {
                        s += i + "\n";
                    }
                    return s;
                }
            }
        }
    }
}