qtcreator design view doesn't display my QML

[Tom asso]

I’m running a very simple QML example, qtcreator’s design view just displays mostly black background, with no actual components visible.
Running Qt Creator 12.0.2 based on Qt 6.6.0, on ubuntu 22.04.3.

main.qml:

import QtQuick 2.15
import QtQuick.Controls 2.15
import QtQuick.Window 2.15

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

    MenuBar {
        id: menuBar
            Menu {
                title: qsTr("&File")
                Action { text: qsTr("&New...") }
                Action { text: qsTr("&Open...") }
                Action { text: qsTr("&Save") }
                Action { text: qsTr("Save &As...") }
                MenuSeparator { }
                Action { text: qsTr("&Quit") }
            }
    }

    RadioButton {
        id: radioButton
        x: 200
        y: 149
        text: qsTr("Radio Button")
    }
}

Pressing qtcreator 'Run' arrow button displays what I expect
However pressing the Design button when main.qml is open shows mostly black where I expect my component layout to be displayed. I looked at qtcreator Edit->Preferences, didn't see any obvious settings that made a difference. What am I doing wrong?
Thanks!

[sierdzio]

Which Qt Creator version is it? Have you used official Qt installer to install it?