The first bug I found was with a mob spawner. I had started a new world with this snapshot and found a Zombie Spawner and I lit the area up so they would stop spawning. But they didnt stop instead of normally spawning on the dungeon floor they spawned in a wall and suffocated.

The next one I found was in the same world and i had made a nether portal and went through it and I turned around at the portal and the portal wasn't lit and the same thing happened when I made a new nether portal in the nether i went through it and the new portal I came out of in the over world wasn't lit.

That's all I found ill post more bug reports if I find any thx for reading.