Popup Menu from QToolButton opens in the primary monitor only.

#include "mainwindow.h"
#include <QToolBar>
#include <QToolButton>
#include <QMenu>

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
{
    QToolBar *tb = new QToolBar;
    addToolBar(tb);

    QToolButton *tool = new QToolButton;
    tb->addWidget(tool);

    tool->setText("Test tool");
    QMenu *menu = new QMenu(tool);
    tool->setMenu(menu);
    menu->addAction("Action 0");
    tool->setPopupMode(QToolButton::ToolButtonPopupMode::InstantPopup);
}

#include "mainwindow.h"

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.resize(800, 600);
    w.show();
    return a.exec();
}