Currently there's a bug that prevents a player from colliding with any entity, which basically means you can not manually push around minecarts, villagers etc to get them where you want. It's been like this for a couple of days now, and I noticed this quite quickly as I use minecarts in a lot of my contraptions, and this needs a quick fix because player collision is necessity.
But as many of you guys know, player collision was readded in 1.9, and many dislike it, so this might've just been an attempt to fix the player collision (issue if you may?). But, it hasn't gone very well if that's the case.
Please fix this!