From 3d9485b9cd411e336dac59b8c0cb9c0bc0d82ceb Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 24 Jan 2018 20:06:39 -0500
Subject: [PATCH] MC-99321 - Dont check for blocked double chest for hoppers
 etc

This is a source of MAJOR lag for hoppers, as well as a gameplay bug.

This removes the necessity to disable the cat on chest behavior to improve performance.

now performance will be improved even if you have cat chest detection on.

diff --git a/src/main/java/net/minecraft/server/BlockChest.java b/src/main/java/net/minecraft/server/BlockChest.java
index 90267a1fb..91d3308c1 100644
--- a/src/main/java/net/minecraft/server/BlockChest.java
+++ b/src/main/java/net/minecraft/server/BlockChest.java
@@ -348,7 +348,7 @@ public class BlockChest extends BlockTileEntity {
                     // Paper end
 
                     if (block == this) {
-                        if (this.e(world, blockposition1)) {
+                        if (!flag && this.e(world, blockposition1)) { // Paper - check for allowBlocked flag - MC-99321
                             return null;
                         }
 
-- 
2.18.0