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QtQuick 2.0 TextEdit, TextArea, both are very-very slow on high-end PC

  • I have a very-very simple code:

    import QtQuick 2.6
    import QtQuick.Controls 1.5
    import QtQuick.Dialogs 1.2
    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();
        TextArea {
            anchors.fill: parent

    If I paste a file of 6000 lines in the TextArea it is works very-very slow and laggy. However, the text scrolls quite fast, the interacting with it (selecting, writing, deleting) works very-very and very slow and freezy.
    What can I do to increase performance? For example, QPlainTextEdit in c++ works much better.

    Qt 5.6, Archlinux x64, i7 4790, 32gb ram.

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