From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: jmp <jasonpenilla2@me.com>
Date: Mon, 5 Apr 2021 18:35:37 -0700
Subject: [PATCH] Allow PlayerEditBookEvent to fire for off hand


diff --git a/src/main/java/org/bukkit/event/player/PlayerEditBookEvent.java b/src/main/java/org/bukkit/event/player/PlayerEditBookEvent.java
index c8fda418bd5e0e6c299900be469862dbc5d7a56f..b8994a6d023c124f2c068d2e69f2c3d949b9405e 100644
--- a/src/main/java/org/bukkit/event/player/PlayerEditBookEvent.java
+++ b/src/main/java/org/bukkit/event/player/PlayerEditBookEvent.java
@@ -24,7 +24,7 @@ public class PlayerEditBookEvent extends PlayerEvent implements Cancellable {
     public PlayerEditBookEvent(@NotNull Player who, int slot, @NotNull BookMeta previousBookMeta, @NotNull BookMeta newBookMeta, boolean isSigning) {
         super(who);
 
-        Validate.isTrue(slot >= -1 && slot <= 8, "Slot must be in range (-1)-8 inclusive");
+        Validate.isTrue(slot == 40 || slot >= -1 && slot <= 8, "Slot must be in range (-1)-8 inclusive"); // Paper - off hand is 40
         Validate.notNull(previousBookMeta, "Previous book meta must not be null");
         Validate.notNull(newBookMeta, "New book meta must not be null");