Mouse click on tooltip showed in QSpinBox::validate causes a crash - c++

Question

I have a custom SpinBox class that extends a functionality of QSpinBox. I'm trying to show a tooltip when the input is correct, that is, show a tooltip in overriden QSpinBox::validate(QString &text, int &pos). But when I do the mouse click on the tooltip the program crashes.
The crash occures in QApplicationPrivate::notifyActiveWindowChange(QWindow *previous), it looks like Qt tries to set QTipLabel (which has already been destroyed) as an active window.
Here is the minimal code to reproduce the crash:
// spinbox.h
#include <QSpinBox>
#include <QToolTip>
class SpinBox : public QSpinBox
{
Q_OBJECT
public:
explicit SpinBox(QWidget *parent = nullptr)
: QSpinBox(parent)
{}
~SpinBox() override = default;
QValidator::State validate(QString &input, int &pos) const override
{
Q_UNUSED(pos);
int x = input.toInt();
auto mn = minimum();
auto mx = maximum();
if(x >= mn && x <= mx)
{
QToolTip::showText(mapToGlobal({0, 0}), QString("Your value fits the range!!!"));
return QValidator::State::Acceptable;
}
else
{
QToolTip::hideText();
}
return QValidator::State::Invalid;
}
};
// constructor of the default mainwindow created by qt creator
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent)
{
Ui::MainWindow ui;
ui.setupUi(this);
auto spin_box = new SpinBox(this);
spin_box->setRange(1, 200);
}
Here is a gif that illustrates the crash:
Thanks in advance!
UPD.
I've found that after clicking on the tooltip, the qtooltip_labelWindow gets focus.
UPD2.
I haven't found the reason of the crash yet, but a workaround that helps me is to install the following event filter to qApp:
bool eventFilter(QObject* obj, QEvent* e) override
{
if(obj->objectName().contains("tooltip") && e->type() == QEvent::FocusIn)
{
if (auto window = qobject_cast<QWindow*>(obj))
window->show();
}
return QObject::eventFilter(obj, e);
}