A commenter on Blizzard Watch asked for others using this addon, saying that for them it was only displaying Suramar pets on the objective list - on a level 21 character in Darkshore. It was difficult to check myself as I have captured most pets, so I flew a character out to Draenor's Nagrand where I knew I did not have some dropped ones. Pet Tracker showed no pets I didn't have, and noted only 2/2. There are far more pets in that zone. I don't know how to test this further without releasing pets.