BauSystem_Main/src/de/steamwar/bausystem/BauSystem.java

@@ -31,7 +31,6 @@ import de.steamwar.bausystem.worlddata.WorldData;
 import de.steamwar.message.Message;
 import lombok.Getter;
 import org.bukkit.Bukkit;
-import org.bukkit.World;
 import org.bukkit.event.Listener;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.java.JavaPlugin;
@@ -53,12 +52,8 @@ public class BauSystem extends JavaPlugin implements Listener {
     @Getter
     private static BauSystem instance;
 
-    private World world;
-
     @Override
     public void onEnable() {
-        world = Bukkit.getWorlds().get(0);
-
         // LOGGER
         fixLogging();
 

BauSystem_Main/src/de/steamwar/bausystem/features/simulator2/gui/base/SimulatorBaseGui.java

@@ -45,14 +45,19 @@ public abstract class SimulatorBaseGui {
     }
 
     public final void open() {
-        if (inv != null && Core.getVersion() > 19) {
+        String newTitle = title();
+        String originalTitle = player.getOpenInventory().getTitle();
+
+        if (inv != null && (newTitle.equals(originalTitle) || Core.getVersion() > 19)) {
             inv.clear();
             setup();
             if (player.getOpenInventory().getTopInventory() != inv) {
                 inventory.open();
                 SimulatorWatcher.watch(player, simulator, this::open);
             }
-            player.getOpenInventory().setTitle(title());
+            if (Core.getVersion() > 19) {
+                player.getOpenInventory().setTitle(title());
+            }
             populate();
             return;
         }