What on earth is this animation in Studio?

Every time I go into play solo mode in Studio my character has this very odd animation and always faces away from the camera unless you hold shift. This happened out of nowhere without any updates to Studio. Happens on blank baseplates as well.

EDIT: Jumping is also nerfed and doesn’t auto-jump when holding down space. Does this have something to do with the new Humanoid property relating to jumping?
Walkspeed is also much faster than normal, it defaults to 1 even though changing it doesn’t affect anything.

Probably a plugin you have.