So the bug appears if you go into 3rd Personview and go all above your player.
Facing : -90.0 and 90 after that you can`t properly move around your player the camera starts to get lost and goes to a like snaping mode.
Here a Video for a better explanation : https://www.youtube.com/watch?v=4h9zFoTHnFg
Thank you for your report!
We're actually already tracking this issue at MC-145668, so we will resolve and link this ticket as a duplicate.
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