QAction::ApplicationSpecificRole demo

mainwindow.c

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include <QAction>
#include <QMenuBar>

#include <iostream>

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);

    auto action = new QAction("Test");
    action->setMenuRole(QAction::ApplicationSpecificRole);
    connect(action, &QAction::triggered, []{ std::cout << "lol" << std::endl; });

    auto file = menuBar()->addMenu("File");

    file->addAction(action);
}

MainWindow::~MainWindow()
{
    delete ui;
}