Definitely readd this patch for the first time

patches/server/0161-handle-PacketPlayInKeepAlive-async.patch

@@ -0,0 +1,40 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Shane Freeder <theboyetronic@gmail.com>
+Date: Thu, 5 Oct 2017 01:54:07 +0100
+Subject: [PATCH] handle PacketPlayInKeepAlive async
+
+In 1.12.2, Mojang moved the processing of PacketPlayInKeepAlive off the main
+thread, while entirely correct for the server, this causes issues with
+plugins which are expecting the PlayerQuitEvent on the main thread.
+
+In order to counteract some bad behavior, we will post handling of the
+disconnection to the main thread, but leave the actual processing of the packet
+off the main thread.
+
+also adding some additional logging in order to help work out what is causing
+random disconnections for clients.
+
+diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+index 24f6aeb862c9384ec11132cdf14ca73ee0762e2e..f188a55fda95abd5ccf9119ed4ab772841128d74 100644
+--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
++++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+@@ -2781,14 +2781,18 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Ser
+ 
+     @Override
+     public void handleKeepAlive(ServerboundKeepAlivePacket packet) {
+-        PacketUtils.ensureRunningOnSameThread(packet, this, this.player.getLevel()); // CraftBukkit
++        //PlayerConnectionUtils.ensureMainThread(packetplayinkeepalive, this, this.player.getWorldServer()); // CraftBukkit // Paper - This shouldn't be on the main thread
+         if (this.keepAlivePending && packet.getId() == this.keepAliveChallenge) {
+             int i = (int) (Util.getMillis() - this.keepAliveTime);
+ 
+             this.player.latency = (this.player.latency * 3 + i) / 4;
+             this.keepAlivePending = false;
+         } else if (!this.isSingleplayerOwner()) {
++            // Paper start - This needs to be handled on the main thread for plugins
++            server.submit(() -> {
+             this.disconnect(new TranslatableComponent("disconnect.timeout"));
++            });
++            // Paper end
+         }
+ 
+     }