So my friend has applied from south africa on February 18/2018 and review of eligibility has been on for a long time, and still days processing application, and have sent a CSE... it's now been 106 days with no answer and there is no background or security check happening, is this normal?
I've just seen your thread in the Permanent Residence section.
No, he won't need to reapply for another TRV if he renews his passport. He needs to inform the visa office about the new passport + the TRV stamped on the new passport would possibly have a longer validity.
IMO, he must reapply for a new passport immediately (if he has not already done so) for two reasons:
1. If approved, his TRV would be for maximum until his the expiry of his current passport = Just a few weeks/months (?) unless he has a new passport
2. It's easier + faster to get a new passport in the home country as compared to applying for one from Canada
As for the delay in getting a response from IRCC, it could take up to 30 days to get a response to a CSE. Hopefully, you've sent an email too to the Pretoria visa office