If a cat grows up and instantly gets in a boat, it will disappear!! I found this bug in my survival world, as I was ferrying cats in my boat across a body of water. I was feeding a kitten for it to grow up, then it did and instantly got in the boat I was using, simultaneously disappearing. It became evident to me that this happened when I heard a meowing sound in the back of my boat. When I tried to break the boat, I accidentally killed the cat as I did not know it was there.  I have had several visual problems with mobs in the past, which are now fixed, but I thought I would point this one out.

Thanks Mojang!!

-CatcherCat