Fix NPE

Fixes ViaVersion/ViaVersion#2751

common/src/main/java/com/viaversion/viabackwards/protocol/protocol1_12_2to1_13/providers/BackwardsBlockEntityProvider.java

@@ -33,6 +33,7 @@ import com.viaversion.viaversion.api.platform.providers.Provider;
 import com.viaversion.viaversion.libs.opennbt.tag.builtin.CompoundTag;
 import com.viaversion.viaversion.libs.opennbt.tag.builtin.IntTag;
 import com.viaversion.viaversion.libs.opennbt.tag.builtin.StringTag;
+import com.viaversion.viaversion.libs.opennbt.tag.builtin.Tag;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -67,7 +68,12 @@ public class BackwardsBlockEntityProvider implements Provider {
      * @param tag      The block entity tag
      */
     public CompoundTag transform(UserConnection user, Position position, CompoundTag tag) throws Exception {
-        String id = (String) tag.get("id").getValue();
+        final Tag idTag = tag.get("id");
+        if (!(idTag instanceof StringTag)) {
+            return tag;
+        }
+
+        String id = (String) idTag.getValue();
         BackwardsBlockEntityHandler handler = handlers.get(id);
         if (handler == null) {
             if (Via.getManager().isDebug()) {

common/src/main/java/com/viaversion/viabackwards/protocol/protocol1_13_2to1_14/packets/EntityPackets1_14.java

@@ -372,7 +372,7 @@ public class EntityPackets1_14 extends LegacyEntityRewriter<Protocol1_13_2To1_14
                 Item item = (Item) meta.getValue();
                 meta.setValue(protocol.getItemRewriter().handleItemToClient(item));
             } else if (type == Types1_13_2.META_TYPES.blockStateType) {
-                int blockstate = (Integer) meta.getValue();
+                int blockstate = meta.value();
                 meta.setValue(protocol.getMappingData().getNewBlockStateId(blockstate));
             }
         });