Epilepsy Warning for the GIF.

I think that the change that makes it so players can't cross 1 block gaps has made it so vehicles misbehave too.

To reproduce (Don't do this if you're epileptic)

1. Tame a horse and equip it with a saddle.

2. Either try to run into a block to move up it, or try to cross a 2 block gap.

3. You have moved wrongly.