I was working toward the Glitter Maniac perk and found, after opening several anniversary gifts, they weren't all counting toward the perk. It appears they can be opened faster than the perk count can handle. From testing, opening 27 gifts only counted 9 times toward the perk count. If I open each gift with a pause between, they seem to count properly. I suspect my anniversary gift perk count could be under counted by a couple thousand