diff --git a/src/data/bedrock/block/DelegatingBlockStateDeserializer.php b/src/data/bedrock/block/DelegatingBlockStateDeserializer.php
index 2c89ec03bb..1844d44fc0 100644
--- a/src/data/bedrock/block/DelegatingBlockStateDeserializer.php
+++ b/src/data/bedrock/block/DelegatingBlockStateDeserializer.php
@@ -26,4 +26,4 @@ namespace pocketmine\data\bedrock\block;
 interface DelegatingBlockStateDeserializer extends BlockStateDeserializer{
 
 	public function getRealDeserializer() : BlockStateDeserializer;
-}
\ No newline at end of file
+}
diff --git a/src/data/bedrock/block/DelegatingBlockStateSerializer.php b/src/data/bedrock/block/DelegatingBlockStateSerializer.php
index fc0788d546..8c53336068 100644
--- a/src/data/bedrock/block/DelegatingBlockStateSerializer.php
+++ b/src/data/bedrock/block/DelegatingBlockStateSerializer.php
@@ -26,4 +26,4 @@ namespace pocketmine\data\bedrock\block;
 interface DelegatingBlockStateSerializer extends BlockStateSerializer{
 
 	public function getRealSerializer() : BlockStateSerializer;
-}
\ No newline at end of file
+}
diff --git a/src/data/bedrock/item/upgrade/ItemIdMetaUpgradeSchema.php b/src/data/bedrock/item/upgrade/ItemIdMetaUpgradeSchema.php
index 74175c560b..a977f4ad29 100644
--- a/src/data/bedrock/item/upgrade/ItemIdMetaUpgradeSchema.php
+++ b/src/data/bedrock/item/upgrade/ItemIdMetaUpgradeSchema.php
@@ -23,6 +23,8 @@ declare(strict_types=1);
 
 namespace pocketmine\data\bedrock\item\upgrade;
 
+use function mb_strtolower;
+
 final class ItemIdMetaUpgradeSchema{
 
 	/**
diff --git a/src/data/bedrock/item/upgrade/R12ItemIdToBlockIdMap.php b/src/data/bedrock/item/upgrade/R12ItemIdToBlockIdMap.php
index bd4866f97f..e3476c9c4a 100644
--- a/src/data/bedrock/item/upgrade/R12ItemIdToBlockIdMap.php
+++ b/src/data/bedrock/item/upgrade/R12ItemIdToBlockIdMap.php
@@ -27,11 +27,11 @@ use pocketmine\utils\AssumptionFailedError;
 use pocketmine\utils\SingletonTrait;
 use pocketmine\utils\Utils;
 use Webmozart\PathUtil\Path;
-use function array_search;
 use function file_get_contents;
 use function is_array;
 use function is_string;
 use function json_decode;
+use function mb_strtolower;
 use const pocketmine\BEDROCK_ITEM_UPGRADE_SCHEMA_PATH;
 
 /**