I was playing on my survival world with the 18w44a snapshot, and I tamed a horse. When I tamed the horse I received the 'Best Friends Forever' advancement but I also recieved the 'A Complete Catalogue' advancement. I have not even seen the new cats or ocelots in this world yet, and when I look in the advancements tab it says I have found 10/10.
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Thank you for your report!
However, this issue is a Duplicate of MC-138541.
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