QTextFrame removal from QTextDocument leads to segmentation fault

#include <QApplication>
#include <QtCore>
#include <QtGui>
#include <QtWidgets>


namespace {

    class TestEdit : public QTextEdit {
    public slots:

        void removeCurrentFrame() {
            QTextCursor cursor = this->textCursor();
            QTextFrame* currentFrame = cursor.currentFrame();
            if (currentFrame != NULL && currentFrame != this->document()->rootFrame()) {
                //delete currentFrame;
                currentFrame->deleteLater();
                qDebug() << "deleted, editor still working?";
            }
        }
    protected:

        virtual void keyPressEvent(QKeyEvent *e) {

            if (e->key() == Qt::Key_X) {

                QTextCursor cursor = this->textCursor();
                QTextFrameFormat frameFormat;
                frameFormat.setBackground(QColor(Qt::red));
                QTextFrame* frame = cursor.insertFrame(frameFormat);

            } else if (e->key() == Qt::Key_Y) {

                removeCurrentFrame();

            }

            QTextEdit::keyPressEvent(e);
        }
    };
}

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QMainWindow* w = new QMainWindow();
    w->setAttribute(Qt::WA_DeleteOnClose);
    TestEdit* testEdit = new TestEdit();
    QWidget* widget = new QWidget(w);
    QVBoxLayout *vLayout = new QVBoxLayout(widget);
    QPushButton *button = new QPushButton("delete current frame");
    vLayout->addWidget(button);
    vLayout->addWidget(testEdit);
    w->setCentralWidget(widget);
    QObject::connect(button, &QAbstractButton::clicked, testEdit, &TestEdit::removeCurrentFrame);
    w->adjustSize();
    w->move(QApplication::desktop()->screen()->rect().center() - w->rect().center());
    w->show();
    return app.exec();
}