#include <QApplication>
#include <QGuiApplication>

#include <QDialog>


int main(int argc, char *argv[])
{ // non-integer device-pixel ratio causes problems when rounded down
  QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::Floor); // problem
//  QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::Ceil); // OKAY
//  QGuiApplication::setHighDpiScaleFactorRoundingPolicy(Qt::HighDpiScaleFactorRoundingPolicy::PassThrough); // OKAY

  // application
  QApplication app(argc,argv);

  // size grip is not shown when device pixel ratio is rounded down
  // tested on 4K screen under Windows 10 with a device pixel ratio 1.5
  QDialog dialog;
  dialog.setSizeGripEnabled(true);
  dialog.show();

  return QApplication::exec();
}