diff --git a/pandalib-core/src/main/java/fr/pandacube/lib/core/json/Json.java b/pandalib-core/src/main/java/fr/pandacube/lib/core/json/Json.java
index 8b16078..8d8b781 100644
--- a/pandalib-core/src/main/java/fr/pandacube/lib/core/json/Json.java
+++ b/pandalib-core/src/main/java/fr/pandacube/lib/core/json/Json.java
@@ -3,6 +3,7 @@ package fr.pandacube.lib.core.json;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 import com.google.gson.JsonParseException;
+import com.google.gson.Strictness;
 import com.google.gson.ToNumberStrategy;
 import com.google.gson.TypeAdapter;
 import com.google.gson.TypeAdapterFactory;
@@ -74,21 +75,21 @@ public class Json {
 	public static final Gson gson = build(Function.identity());
 
 	/**
-	 * {@link Gson} instance with {@link GsonBuilder#setLenient()}, {@link GsonBuilder#setPrettyPrinting()} and support
+	 * {@link Gson} instance with {@link Strictness#LENIENT}, {@link GsonBuilder#setPrettyPrinting()} and support
 	 * for Java records and additional {@link TypeAdapterFactory} provided with
 	 * {@link #registerTypeAdapterFactory(TypeAdapterFactory)}.
 	 */
 	public static final Gson gsonPrettyPrinting = build(GsonBuilder::setPrettyPrinting);
 
 	/**
-	 * {@link Gson} instance with {@link GsonBuilder#setLenient()}, {@link GsonBuilder#serializeNulls()} and support for
+	 * {@link Gson} instance with {@link Strictness#LENIENT}, {@link GsonBuilder#serializeNulls()} and support for
 	 * Java records and additional {@link TypeAdapterFactory} provided with
 	 * {@link #registerTypeAdapterFactory(TypeAdapterFactory)}.
 	 */
 	public static final Gson gsonSerializeNulls = build(GsonBuilder::serializeNulls);
 
 	/**
-	 * {@link Gson} instance with {@link GsonBuilder#setLenient()}, {@link GsonBuilder#serializeNulls()},
+	 * {@link Gson} instance with {@link Strictness#LENIENT}, {@link GsonBuilder#serializeNulls()},
 	 * {@link GsonBuilder#setPrettyPrinting()} and support for Java records and additional {@link TypeAdapterFactory}
 	 * provided with {@link #registerTypeAdapterFactory(TypeAdapterFactory)}.
 	 */
@@ -105,7 +106,7 @@ public class Json {
 				.registerTypeAdapterFactory(new CustomAdapterFactory())
 				.disableHtmlEscaping()
 				.setObjectToNumberStrategy(YAML_EQUIVALENT_NUMBER_STRATEGY)
-				.setLenient();
+				.setStrictness(Strictness.LENIENT);
 		return builderModifier.apply(base).create();
 	}
 
diff --git a/pandalib-paper/src/main/java/fr/pandacube/lib/paper/json/ItemStackAdapter.java b/pandalib-paper/src/main/java/fr/pandacube/lib/paper/json/ItemStackAdapter.java
index 14168a0..5bb5a02 100644
--- a/pandalib-paper/src/main/java/fr/pandacube/lib/paper/json/ItemStackAdapter.java
+++ b/pandalib-paper/src/main/java/fr/pandacube/lib/paper/json/ItemStackAdapter.java
@@ -38,15 +38,13 @@ import java.util.Map;
         if (!(json instanceof JsonObject jsonObj))
             throw new JsonParseException("Unable to deserialize a ConfigurationSerializable from the provided json structure.");
 
-        // the deserialized json may contain older data compatible with pre 1.21.5 but not compatible after.
         // if it contains both old and new data, delete the old one introduced for compatibility
-        if (jsonObj.has("DataVersion")) { // it uses the new DataVersion data
+        if (jsonObj.has("DataVersion") || jsonObj.has("id")) {
             jsonObj.remove("v");
-        }
-        if (jsonObj.has("id")) {
             jsonObj.remove("type");
         }
 
+        // format used when using ConfigurationSerialization
         if (jsonObj.has(ConfigurationSerialization.SERIALIZED_TYPE_KEY))
             return context.deserialize(jsonObj, ConfigurationSerializable.class);
 
@@ -79,17 +77,7 @@ import java.util.Map;
 
     @Override
     public JsonElement serialize(ItemStack src, Type typeOfSrc, JsonSerializationContext context) {
-        Map<String, Object> serialized = src.serialize();
-
-        // make the generated json compatible with pre 1.21.5 deserializer (temporary fix during the upgrade of the server)
-        if (serialized.containsKey("DataVersion")) {
-            serialized.put("v", serialized.get("DataVersion"));
-        }
-        if (serialized.containsKey("id")) {
-            serialized.put("type", Registry.MATERIAL.getOrThrow(Key.key((String)serialized.get("id"))).name());
-        }
-
-        return context.serialize(serialized, MAP_STR_OBJ_TYPE.getType());
+        return context.serialize(src.serialize(), MAP_STR_OBJ_TYPE.getType());
     }