Recently flew TAP from YYZ to LIS. LIS to OPO, OPP to LIS. Then LIS to YYZ.
For flights within Portugal (ie. Between LIS and OPO), during boarding, they did check to make sure carry on luggage fit within the sizer (only luggage with wheels not duffle type bags). This did make a few people angry as they had to pay extra and check in their carry on I did not see carry on or personal items being weighed.
Prior to my trip I was worried about the limit as I did some research online and read many complaints, again mostly for flights within Portugal.
Hope this helps!