Using Qt 6 QPromise and QFuture

Question

I am trying to use Qt 6 QPromise (as described in https://www.qt.io/blog/asynchronous-apis-in-qt-6):

   QPromise<QByteArray> promise;
   QFuture<QByteArray> future = promise.future();

   promise.start();
   qDebug() << "Pre timer";
   QTimer::singleShot(2000, this, [p = std::move(promise)]()
   {
       qDebug() << "Timer triggered";
       p.finish(); // error
   });

But p.finish() triggers a compilation error:

error C2662: 'void QPromise<QByteArray>::finish(void)': cannot convert 'this' pointer from 'const QPromise<QByteArray>' to 'QPromise<QByteArray> &'

Is the example code (from the blog entry) wrong, or did I miss something?

Regards,