Fix plain SHULKER_BOX not treated as shulker box, voiding its contents

src/main/java/com/yourname/sellplugin/SellPlugin.java

@@ -28,6 +28,7 @@ public class SellPlugin extends JavaPlugin {
     public void onEnable() {
         saveDefaultConfig();
         configManager = new ConfigManager(this);
+        configManager.generateExampleConfig();
 
         priceManager = new PriceManager(this);
         priceManager.loadPrices();

src/main/java/com/yourname/sellplugin/gui/CategoryItemsGUI.java

@@ -223,7 +223,8 @@ private ItemStack resolveItemStack(String itemKey) {
             return item;
         }
         Material mat = Material.matchMaterial(itemKey);
-        return new ItemStack(mat != null ? mat : Material.BARRIER);
+        if (mat == null || !mat.isItem()) return new ItemStack(Material.BARRIER);
+        return new ItemStack(mat);
     }
 
     // ── Item clicked ─────────────────────────────────────────────────────────

src/main/java/com/yourname/sellplugin/gui/GUIListener.java

@@ -81,7 +81,7 @@ public void onClick(InventoryClickEvent e) {
                     e.setCancelled(true);
                     String catId = shopGUI.getCategoryAtSlot(slot);
                     if (catId != null) {
-                        new CategoryItemsGUI(plugin, player, catId, 0).open(player);
+                        new CategoryProgressGUI(plugin, player, catId).open(player);
                     }
                     return;
                 }

src/main/java/com/yourname/sellplugin/listener/WorthPacketListener.java

@@ -16,6 +16,7 @@
 import com.yourname.sellplugin.gui.ShopMainGUI;
 import com.yourname.sellplugin.gui.TopSellGUI;
 import com.yourname.sellplugin.util.NumberFormatter;
+import org.bukkit.GameMode;
 import org.bukkit.block.DoubleChest;
 import org.bukkit.entity.Player;
 import org.bukkit.event.inventory.InventoryType;
@@ -46,14 +47,16 @@ public void register() {
         ProtocolManager protocolManager = ProtocolLibrary.getProtocolManager();
         packetListener = new PacketAdapter(plugin, ListenerPriority.NORMAL,
                 PacketType.Play.Server.SET_SLOT,
+                PacketType.Play.Server.SET_CURSOR_ITEM,
                 PacketType.Play.Server.WINDOW_ITEMS) {
 
             @Override
             public void onPacketSending(PacketEvent event) {
                 if (!WorthPacketListener.this.plugin.getConfigManager().isWorthEnabled()) return;
                 if (!shouldDecorate(event.getPlayer())) return;
 
-                if (event.getPacketType() == PacketType.Play.Server.SET_SLOT) {
+                if (event.getPacketType() == PacketType.Play.Server.SET_SLOT
+                        || event.getPacketType() == PacketType.Play.Server.SET_CURSOR_ITEM) {
                     if (event.getPacket().getItemModifier().size() <= 0) return;
                     ItemStack item = event.getPacket().getItemModifier().read(0);
                     ItemStack updated = addWorthLore(event.getPlayer(), item);
@@ -111,6 +114,8 @@ private ItemStack addWorthLore(Player player, ItemStack original) {
     }
 
     private boolean shouldDecorate(Player player) {
+        if (player.getGameMode() == GameMode.CREATIVE) return false;
+
         Inventory topInventory = player.getOpenInventory().getTopInventory();
         InventoryHolder holder = topInventory.getHolder();
 

src/main/java/com/yourname/sellplugin/manager/ConfigManager.java

@@ -224,6 +224,23 @@ public List<String> getIconLore(String key, List<String> defaultLore) {
     public void reload() {
         plugin.reloadConfig();
         plugin.getPriceManager().loadPrices();
+        generateExampleConfig();
+    }
+
+    /**
+     * Generates an example-config.yml in the plugin data folder that always
+     * reflects the latest defaults shipped inside the JAR.
+     */
+    public void generateExampleConfig() {
+        try {
+            java.io.InputStream in = plugin.getResource("config.yml");
+            if (in == null) return;
+            java.io.File target = new java.io.File(plugin.getDataFolder(), "example-config.yml");
+            java.nio.file.Files.copy(in, target.toPath(), java.nio.file.StandardCopyOption.REPLACE_EXISTING);
+            in.close();
+        } catch (java.io.IOException e) {
+            plugin.getLogger().warning("Could not generate example-config.yml: " + e.getMessage());
+        }
     }
 
     // ---- Helpers ----------------------------------------------------------

src/main/java/com/yourname/sellplugin/manager/SellManager.java

@@ -307,9 +307,11 @@ public void sendSellNotification(Player player, double amount, int itemCount) {
     // Shulker box helpers
     // ---------------------------------------------------------------
 
-    /** Returns true if the item is any colour of shulker box. */
+    /** Returns true if the item is any colour of shulker box (including the non-dyed SHULKER_BOX). */
     public static boolean isShulkerBox(ItemStack item) {
-        return item != null && item.getType().name().endsWith("_SHULKER_BOX");
+        if (item == null) return false;
+        String name = item.getType().name();
+        return name.equals("SHULKER_BOX") || name.endsWith("_SHULKER_BOX");
     }
 
     /**

src/main/resources/price.yml

@@ -68,7 +68,7 @@ armortools:
   FLINT_AND_STEEL: 6
   ROCKET: 6
   LEAD: 5
-  POWDER_SNOW: 5
+  POWDER_SNOW_BUCKET: 5
   SHEARS: 4
   SPYGLASS: 50
   COMPASS: 10.0