While testing the fix to chests not spawning in dungeons (thank you Mojang for correcting the type-o 😃) lead me to discovering that some chests are broken within some of the spawner rooms (leaving the items on the ground to despawn) when compared to their 1.7.4 generation
Also dungeons with sand or gravel falling into them are missing their cobble / mosey cobble stone floor / monster spawner; and seemingly are being overwritten by the falling sand / gravel..
Seed -6361266393149821128 (xyz) -42 / 23 / 827 & -596 27 -322
Seed -1082223639696259069 (xyz) -748 60 -91
No sad or gravel was involved in this latest find... one of the chests is missing? and the contents of it are scattered on the floor.
Seed 8632520611045298466 (xyz) 1700 27 -583
I've been finding these, too. Just for the last couple days. I went back and found one after respawning the world to make sure it wasn't from a creeper or something. I attached the picture. When I dug out the sand that appears to be where the chests and spawner would be, there's mossy floor under it. When I dug out the rest of the sand, there was no floor under that.The sand seems to have replaced the uppermost layer of the dungeon. Yesterday, my starting chest was exploded.