diff --git a/bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_20_5to1_21/PlayerChangeItemListener.java b/bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_20_5to1_21/PlayerChangeItemListener.java
new file mode 100644
index 000000000..d2b52a8b2
--- /dev/null
+++ b/bukkit/src/main/java/com/viaversion/viaversion/bukkit/listeners/v1_20_5to1_21/PlayerChangeItemListener.java
@@ -0,0 +1,92 @@
+/*
+ * This file is part of ViaVersion - https://github.com/ViaVersion/ViaVersion
+ * Copyright (C) 2016-2024 ViaVersion and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+package com.viaversion.viaversion.bukkit.listeners.v1_20_5to1_21;
+
+import com.viaversion.viaversion.ViaVersionPlugin;
+import com.viaversion.viaversion.api.Via;
+import com.viaversion.viaversion.api.connection.UserConnection;
+import com.viaversion.viaversion.api.protocol.packet.PacketWrapper;
+import com.viaversion.viaversion.api.type.Types;
+import com.viaversion.viaversion.bukkit.listeners.ViaBukkitListener;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.Protocol1_20_5To1_21;
+import com.viaversion.viaversion.protocols.v1_20_5to1_21.packet.ClientboundPackets1_21;
+import io.papermc.paper.event.player.PlayerInventorySlotChangeEvent;
+import org.bukkit.NamespacedKey;
+import org.bukkit.enchantments.Enchantment;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.player.PlayerItemHeldEvent;
+import org.bukkit.inventory.ItemStack;
+
+/**
+ * For some reason, mining efficiency is not calculated by the client anymore, but by the server,
+ * then sending the current value to the client every time the item changes. This roughly emulates that behavior.
+ */
+public final class PlayerChangeItemListener extends ViaBukkitListener {
+
+    private static final int MINING_EFFICIENCY_ID = 19;
+    private final Enchantment efficiency = Enchantment.getByKey(NamespacedKey.minecraft("efficiency"));
+
+    public PlayerChangeItemListener(final ViaVersionPlugin plugin) {
+        super(plugin, Protocol1_20_5To1_21.class);
+    }
+
+    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
+    public void onPlayerInventorySlotChangedEvent(final PlayerInventorySlotChangeEvent event) {
+        final Player player = event.getPlayer();
+        final ItemStack item = event.getNewItemStack();
+        if (event.getSlot() == player.getInventory().getHeldItemSlot()) {
+            sendAttributeUpdate(player, item);
+        }
+    }
+
+    @EventHandler(priority = EventPriority.MONITOR, ignoreCancelled = true)
+    public void onPlayerItemHeld(final PlayerItemHeldEvent event) {
+        final Player player = event.getPlayer();
+        final ItemStack item = player.getInventory().getItem(event.getNewSlot());
+        sendAttributeUpdate(player, item != null ? item : ItemStack.empty());
+    }
+
+    private void sendAttributeUpdate(final Player player, final ItemStack item) {
+        final UserConnection connection = Via.getAPI().getConnection(player.getUniqueId());
+        if (connection == null || !isOnPipe(player)) {
+            return;
+        }
+
+        final int efficiencyLevel = item.getEnchantmentLevel(efficiency);
+        final PacketWrapper attributesPacket = PacketWrapper.create(ClientboundPackets1_21.UPDATE_ATTRIBUTES, connection);
+        attributesPacket.write(Types.VAR_INT, player.getEntityId());
+
+        attributesPacket.write(Types.VAR_INT, 1); // Size
+        attributesPacket.write(Types.VAR_INT, MINING_EFFICIENCY_ID); // Attribute ID
+        attributesPacket.write(Types.DOUBLE, 0D); // Base
+
+        if (efficiencyLevel > 0) {
+            final double modifierAmount = (efficiencyLevel * efficiencyLevel) + 1D;
+            attributesPacket.write(Types.VAR_INT, 1); // Modifiers
+            attributesPacket.write(Types.STRING, "minecraft:enchantment.efficiency/mainhand"); // Id
+            attributesPacket.write(Types.DOUBLE, modifierAmount);
+            attributesPacket.write(Types.BYTE, (byte) 0); // 'Add' operation
+        } else {
+            attributesPacket.write(Types.VAR_INT, 0); // Modifiers
+        }
+
+        attributesPacket.scheduleSend(Protocol1_20_5To1_21.class);
+    }
+}
diff --git a/bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/BukkitViaLoader.java b/bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/BukkitViaLoader.java
index 6f6045478..9f56fd9ab 100644
--- a/bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/BukkitViaLoader.java
+++ b/bukkit/src/main/java/com/viaversion/viaversion/bukkit/platform/BukkitViaLoader.java
@@ -33,6 +33,7 @@ import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.BlockListener
 import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.DeathListener;
 import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.HandItemCache;
 import com.viaversion.viaversion.bukkit.listeners.protocol1_9to1_8.PaperPatch;
+import com.viaversion.viaversion.bukkit.listeners.v1_20_5to1_21.PlayerChangeItemListener;
 import com.viaversion.viaversion.bukkit.providers.BukkitAckSequenceProvider;
 import com.viaversion.viaversion.bukkit.providers.BukkitBlockConnectionProvider;
 import com.viaversion.viaversion.bukkit.providers.BukkitInventoryQuickMoveProvider;
@@ -176,6 +177,9 @@ public class BukkitViaLoader implements ViaPlatformLoader {
             Via.getManager().getProviders().use(AckSequenceProvider.class, new BukkitAckSequenceProvider(plugin));
             new BlockBreakListener(plugin).register();
         }
+        if (serverProtocolVersion.olderThan(ProtocolVersion.v1_21) && PaperViaInjector.hasClass("io.papermc.paper.event.player.PlayerInventorySlotChangeEvent")) {
+            new PlayerChangeItemListener(plugin).register();
+        }
     }
 
     private boolean hasGetHandMethod() {