Slime Block/Sticky Piston Bug

Put the summary of the bug you're having here

*What I expected to happen was the slime would be pulled normally up and down.

*What actually happened was the slime would not move or attatch to the piston even though it was 12 blocks.

Steps to Reproduce:
1. Just make a bunch of sticky pistons and slime and make it 2 by 3 for the slime.
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