QPlainTextEdit: long placeholder text doesn't auto-wrap

#include <QApplication>
#include <QMainWindow>
#include <QPlainTextEdit>

int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	QMainWindow w;

	auto textEdit = new QPlainTextEdit(&w);
	textEdit->setLineWrapMode(QPlainTextEdit::WidgetWidth);
	textEdit->setPlaceholderText("abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc abc");

	w.setCentralWidget(textEdit);
	w.show();

	return a.exec();
}