Paper/patches/server/0517-Remove-stale-POIs.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sat, 9 Jan 2021 14:17:07 +0100
Subject: [PATCH] Remove stale POIs


diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index 902f3a7ae5ba9c15b634bb2f214be7d85c6d5a00..efbdcaff160e1c8e666d54a9babe35ac325ec8a5 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -2103,6 +2103,11 @@ public class ServerLevel extends Level implements WorldGenLevel {
             });
             optional1.ifPresent((holder) -> {
                 this.getServer().execute(() -> {
+                    // Paper start
+                    if (optional.isEmpty() && this.getPoiManager().exists(blockposition1, poiType -> true)) {
+                        this.getPoiManager().remove(blockposition1);
+                    }
+                    // Paper end
                     this.getPoiManager().add(blockposition1, holder);
                     DebugPackets.sendPoiAddedPacket(this, blockposition1);
                 });