If like me, you were sad to see that PetBattle Teams was no longer working after 6.1 deployed yesterday (and this is an AddOn that I highly recommend if you’re into pet battles at all) you can find a fix here:
To fix this for 6.1:
1. Open Interface\AddOns\PetBattleTeams\modules\GUI\GUI.lua
2. Search and replace (ctrl+f or search/replace with your text editor) every “Blizzard_PetJournal” with “Blizzard_Collections”
There are 5 of them in the file. Make sure “Blizzard_Collections” is capitalized like that and that the _ is an underscore and not a hyphen.