A certain user mentioned recently that installing, nuOpera might preserve your Presto notes as a file - somewhere within its folders.
@leocg?If you have Opera Presto and install Opera Blink, a html file with your notes is created on your desktop. Or used to be at least.
I believe I was that "certain user," and I did find that to be true when I upgraded from v. 12.16 to v. 32--once I right-clicked on the desktop and clicked View, then Show desktop icons.