qqmlenginedebugservice assert m_engines.contains(engine)

ASSERT: "m_engines.contains(engine)" in file qqmlenginedebugservice.cpp, line 803 global\qglobal.cpp: 3049

import QtQuick 2.9
import QtQuick.Window 2.2

Window {
    visible: true
    width: 640
    height: 480
    title: qsTr("Hello World")
    property Component x: Qt.createComponent("x.qml")
    Component.onDestruction: console.log(x.createObject(this, {}));
}