AgreeI think you can't make generic statements on this issue. It probably depends on individual status, for example if your work permit expires during PR processing, you may be able to continue working, but if you leave Canada, you'll immediately lose legal status inland and as a consequence, CIC may abandon your application.
CIC web page has the following info:
Can I leave Canada while IRCC processes my application for permanent residence?
Yes. However, if you leave Canada while your application is being processed, you must meet all the admissibility rules before being allowed back into Canada.
If you leave Canada and want to return, you must have all the required documents to enter. This can include:
If you are unable to return to Canada, we could determine that you abandoned your application. In that case, we will not process it.
- a valid passport or other travel documents,
- a valid work permit or study permit, if you need one, and
- a valid visitor visa or an Electronic Travel Authorization (eTA), if you need one.