More than 2 parrots on you causes the extra parrot to Disappear

https://youtu.be/PgTZepSxrac

if you have 2 parrots on your shulders and then add one more the additional one dissapears, gone out of existence
Steps:
1. get 2 parrots to stand on you
2. add 1 more to you by rightclicking it
3. the third parrot you just added will disappear