Does it make a sound when you place it?
Obviously, There is 2 ways this could happen.
The event loop has an exception while loading chunks, so it skips the process, and the blocks that are supposed to load as you see them (That's why this didn't turn up in 1.7) don't load.
The event loop is lagging, which, sometimes, doesn't affect KeyPress or Mouse-1/Mouse-2 bindings, (which means that the game would still be playable) but the event loop still has to load blocks, which would be stuck/not running very fast
If no sound is played when you place blocks, it is 2
But you could use absolute coordinates so that you can set the player's spawn to a place without any blocks
The filter does not cause this. It is caused by the game not detecting that certian mobs are babies and placing the head where a normal zombie/standing mob's head would be
I'm sorry I didn't notice 😛
This is not a Duplicate
They have fixed MC-2664. but not completely
It still bugs with Baby Zombie Villagers
Other mobs will burn and emit light even if it is light out
Maybe if you used c=1 too in your selector, it would know you are only trying to show one score. This could be related to Minecraft avoiding showing multiple scores.