FMA

I was having this show up as well.

[04:53:42] [Server thread/WARN]: Fetching packet for removed entity awb['Air'/8000, l='world', x=-1470.17, y=69.00, z=1405.83]

Went to those coordinates, it is where I had a bunch of chickens penned up over hoppers. The chest the hoppers fed into was full and most of the hoppers were full as well. Perhaps this was coming up whenever an egg that did not get pulled into a hopper despawned.

This is an Optifine issue. Disabling the preview version of Optifine should resolve the problem.

This is in Optifine issue, not a Minecraft issue. Disabling the Optifine preview version you are using will fix the problem.

Problem exists in 14w17a as well

Same problem. Chests positioned as in the screenshot above cannot be opened without first removing an item frame.

Glad to see I'm not alone on this one.