And AddTo is a different event than RemoveFrom

Spigot-Server-Patches/0115-Entity-AddTo-RemoveFrom-World-Events.patch

@@ -1,18 +1,18 @@
-From d57d1c515d1fbe5155a0a161481a6055822d5222 Mon Sep 17 00:00:00 2001
+From 69cf18ad66c779257169488bd09dc7398872b897 Mon Sep 17 00:00:00 2001
 From: Aikar <aikar@aikar.co>
 Date: Mon, 28 Mar 2016 20:32:58 -0400
 Subject: [PATCH] Entity AddTo/RemoveFrom World Events
 
 
 diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
-index fcd7cd6..9d4a92f 100644
+index fcd7cd6..fa84bad 100644
 --- a/src/main/java/net/minecraft/server/World.java
 +++ b/src/main/java/net/minecraft/server/World.java
 @@ -1119,6 +1119,7 @@ public abstract class World implements IBlockAccess {
          }
  
          entity.valid = true; // CraftBukkit
-+        new com.destroystokyo.paper.event.entity.EntityRemoveFromWorldEvent(entity.getBukkitEntity()).callEvent(); // Paper - fire while valid
++        new com.destroystokyo.paper.event.entity.EntityAddToWorldEvent(entity.getBukkitEntity()).callEvent(); // Paper - fire while valid
      }
  
      protected void c(Entity entity) {