diff --git a/src/pocketmine/network/mcpe/protocol/InventoryTransactionPacket.php b/src/pocketmine/network/mcpe/protocol/InventoryTransactionPacket.php
index cd6bddc97..2c423397a 100644
--- a/src/pocketmine/network/mcpe/protocol/InventoryTransactionPacket.php
+++ b/src/pocketmine/network/mcpe/protocol/InventoryTransactionPacket.php
@@ -26,6 +26,7 @@ namespace pocketmine\network\mcpe\protocol;
 #include <rules/DataPacket.h>
 
 use pocketmine\network\mcpe\NetworkSession;
+use pocketmine\network\mcpe\protocol\types\ContainerIds;
 use pocketmine\network\mcpe\protocol\types\NetworkInventoryAction;
 use function count;
 
@@ -74,7 +75,25 @@ class InventoryTransactionPacket extends DataPacket{
 		$this->transactionType = $this->getUnsignedVarInt();
 
 		for($i = 0, $count = $this->getUnsignedVarInt(); $i < $count; ++$i){
-			$this->actions[] = (new NetworkInventoryAction())->read($this);
+			$this->actions[] = $action = (new NetworkInventoryAction())->read($this);
+
+			if(
+				$action->sourceType === NetworkInventoryAction::SOURCE_CONTAINER and
+				$action->windowId === ContainerIds::UI and
+				$action->inventorySlot === 50
+			){
+				$this->isCraftingPart = true;
+				if(!$action->oldItem->isNull() and $action->newItem->isNull()){
+					$this->isFinalCraftingPart = true;
+				}
+			}elseif(
+				$action->sourceType === NetworkInventoryAction::SOURCE_TODO and (
+					$action->windowId === NetworkInventoryAction::SOURCE_TYPE_CRAFTING_RESULT or
+					$action->windowId === NetworkInventoryAction::SOURCE_TYPE_CRAFTING_USE_INGREDIENT
+				)
+			){
+				$this->isCraftingPart = true;
+			}
 		}
 
 		$this->trData = new \stdClass();
diff --git a/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php b/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php
index ecd9eff5d..54ca69682 100644
--- a/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php
+++ b/src/pocketmine/network/mcpe/protocol/types/NetworkInventoryAction.php
@@ -23,6 +23,7 @@ declare(strict_types=1);
 
 namespace pocketmine\network\mcpe\protocol\types;
 
+use pocketmine\inventory\CraftingGrid;
 use pocketmine\inventory\transaction\action\CreativeInventoryAction;
 use pocketmine\inventory\transaction\action\DropItemAction;
 use pocketmine\inventory\transaction\action\InventoryAction;
@@ -36,7 +37,6 @@ class NetworkInventoryAction{
 
 	public const SOURCE_WORLD = 2; //drop/pickup item entity
 	public const SOURCE_CREATIVE = 3;
-	public const SOURCE_CRAFTING_GRID = 100;
 	public const SOURCE_TODO = 99999;
 
 	/**
@@ -108,17 +108,8 @@ class NetworkInventoryAction{
 				break;
 			case self::SOURCE_CREATIVE:
 				break;
-			case self::SOURCE_CRAFTING_GRID:
 			case self::SOURCE_TODO:
 				$this->windowId = $packet->getVarInt();
-				switch($this->windowId){
-					/** @noinspection PhpMissingBreakStatementInspection */
-					case self::SOURCE_TYPE_CRAFTING_RESULT:
-						$packet->isFinalCraftingPart = true;
-					case self::SOURCE_TYPE_CRAFTING_USE_INGREDIENT:
-						$packet->isCraftingPart = true;
-						break;
-				}
 				break;
 			default:
 				throw new \UnexpectedValueException("Unknown inventory action source type $this->sourceType");
@@ -146,7 +137,6 @@ class NetworkInventoryAction{
 				break;
 			case self::SOURCE_CREATIVE:
 				break;
-			case self::SOURCE_CRAFTING_GRID:
 			case self::SOURCE_TODO:
 				$packet->putVarInt($this->windowId);
 				break;
@@ -173,9 +163,31 @@ class NetworkInventoryAction{
 		}
 		switch($this->sourceType){
 			case self::SOURCE_CONTAINER:
-				$window = $player->getWindow($this->windowId);
+				if($this->windowId === ContainerIds::UI and $this->inventorySlot > 0){
+					if($this->inventorySlot === 50){
+						return null; //useless noise
+					}
+					if($this->inventorySlot >= 28 and $this->inventorySlot <= 31){
+						$window = $player->getCraftingGrid();
+						if($window->getGridWidth() !== CraftingGrid::SIZE_SMALL){
+							throw new \UnexpectedValueException("Expected small crafting grid");
+						}
+						$slot = $this->inventorySlot - 28;
+					}elseif($this->inventorySlot >= 32 and $this->inventorySlot <= 40){
+						$window = $player->getCraftingGrid();
+						if($window->getGridWidth() !== CraftingGrid::SIZE_BIG){
+							throw new \UnexpectedValueException("Expected big crafting grid");
+						}
+						$slot = $this->inventorySlot - 32;
+					}else{
+						throw new \UnexpectedValueException("Unhandled magic UI slot offset $this->inventorySlot");
+					}
+				}else{
+					$window = $player->getWindow($this->windowId);
+					$slot = $this->inventorySlot;
+				}
 				if($window !== null){
-					return new SlotChangeAction($window, $this->inventorySlot, $this->oldItem, $this->newItem);
+					return new SlotChangeAction($window, $slot, $this->oldItem, $this->newItem);
 				}
 
 				throw new \UnexpectedValueException("Player " . $player->getName() . " has no open container with window ID $this->windowId");
@@ -199,7 +211,6 @@ class NetworkInventoryAction{
 				}
 
 				return new CreativeInventoryAction($this->oldItem, $this->newItem, $type);
-			case self::SOURCE_CRAFTING_GRID:
 			case self::SOURCE_TODO:
 				//These types need special handling.
 				switch($this->windowId){