They most likely saw your previous visa refusal but thought it was insufficient to deny a PR application. Several reasons may have played on in the visa officer's head before they decided not to take it up against you.
Due to the COVID-19 pandemic, international travel in my country was banned. I was not able to land in Canada and my COPR expired.
International flights here restarted and I applied for a COPR extension. Can IRCC go through my file again and see if there was any overlooked misrepresentation?