No Name1

Ok.

They both have inGround set to 1b.

Confirmed for this.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:MinecartRideable,DisplayTile:sand,CustomDisplayTile:1,DisplayOffset:30}}

Minecart with display tile offset.

Confirmed for 16w03a.

Confirmed for 1.9.

How about ender dragons? They probebly won't have this problem.

Confirmed for EnderCrystal.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:EnderCrystal,Glowing:1}}

.

Because the falling sand is on the boat's hitbox.

I mean big AreaEffectCloud entities.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:AreaEffectCloud,Duration:2147483647,Radius:101f,Particle:"flame"}}

This very big AreaEffectCloud is surely jutting out.

It's because OnGround is set to 0b.

I'm always, running the latest snapshot. The AreaEffectCloud can only be seen when you press F3+B.

Why? It's just,a spawner with technical entities inside! Like AreaEffectCloud with Radius:5f tag, and other entities. And slime which are very big, ender dragon, etc. If you don't want them to spawn, then this command will do.

/gamerule doMobSpawning false

They are now for display.

Something important, what are LightningBolt datatags, do they have tags, like Fire Air OnGround Pos Motion FallDistance Invulnerable Passengers and more? So do they have those tags? .

I hope this gets fixed soon, I really need it.

Why? Do you need it? (Why do you need it?). It's useless anyway. Confirmed for the latest snapshot. As the elytra is only for players.

They aren't supposed, to have elytra.

It's because the zombie pigman thinks, that the player attacked, it so that's why this will happen.

Very big slimes, still have body jut out.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:Slime,Size:8,PersistenceRequired:1}}

AreaEffectCloud still have it's hitbox out (visible through F3+B).

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:AreaEffectCloud,Duration:2147483647,Radius:8f,Particle:"flame"}}

Big jockeys, still have heads, that jut out.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:Skeleton,PersistenceRequired:1}}

This thing still render out.

/setblock ~ ~1 ~ minecraft:mob_spawner 0 replace {SpawnData:{id:ThrownEgg}}

.

Ender dragon spawners still have the dragon head and tail jutting out. And the dragon head seems to point into the spawner, and the tail points out.

Lightning bolts aren't entities. They are just, nothing. It's not an entity, it's just,a random texture that cannot do anything.

Because lightning bolts are invalid entities. They aren't even entities (try viewing it's NBT data and @e cannot target it!).