From fd13ef62c84afb65c43b4137b0208f5ee5601bfd Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 19 Jul 2018 01:08:05 -0400
Subject: [PATCH] Re-add vanilla entity warnings for duplicates

These are a critical sign that somethin went wrong, and you've lost some data....

We should kind of know about these things you know.

diff --git a/src/main/java/net/minecraft/server/WorldServer.java b/src/main/java/net/minecraft/server/WorldServer.java
index c5da81f770..1ac79158c1 100644
--- a/src/main/java/net/minecraft/server/WorldServer.java
+++ b/src/main/java/net/minecraft/server/WorldServer.java
@@ -973,7 +973,8 @@ public class WorldServer extends World {
         if (entity1 == null) {
             return false;
         } else {
-            // WorldServer.LOGGER.warn("Keeping entity {} that already exists with UUID {}", EntityTypes.getName(entity1.getEntityType()), entity.getUniqueID().toString()); // CraftBukkit
+            WorldServer.LOGGER.error("Keeping entity {} that already exists with UUID {}", EntityTypes.getName(entity1.getEntityType()), entity.getUniqueID().toString()); // CraftBukkit // paper
+            WorldServer.LOGGER.error("Deleting duplicate entity {}", entity); // CraftBukkit // paper
             return true;
         }
     }
-- 
2.21.0