diff --git a/src/com/badlogic/gdx/backends/lwjgl3/Lwjgl3Application.java b/src/com/badlogic/gdx/backends/lwjgl3/Lwjgl3Application.java
new file mode 100644
index 000000000..377991265
--- /dev/null
+++ b/src/com/badlogic/gdx/backends/lwjgl3/Lwjgl3Application.java
@@ -0,0 +1,676 @@
+/*******************************************************************************
+ * Copyright 2011 See AUTHORS file.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ ******************************************************************************/
+
+package com.badlogic.gdx.backends.lwjgl3;
+
+import java.io.File;
+import java.io.PrintStream;
+import java.lang.reflect.Method;
+import java.nio.IntBuffer;
+
+import com.badlogic.gdx.ApplicationLogger;
+import com.badlogic.gdx.backends.lwjgl3.audio.Lwjgl3Audio;
+import com.badlogic.gdx.backends.lwjgl3.audio.OpenALLwjgl3Audio;
+import com.badlogic.gdx.graphics.glutils.GLVersion;
+
+import org.lwjgl.BufferUtils;
+import org.lwjgl.glfw.GLFW;
+import org.lwjgl.glfw.GLFWErrorCallback;
+import org.lwjgl.opengl.AMDDebugOutput;
+import org.lwjgl.opengl.ARBDebugOutput;
+import org.lwjgl.opengl.GL;
+import org.lwjgl.opengl.GL11;
+import org.lwjgl.opengl.GL43;
+import org.lwjgl.opengl.GLCapabilities;
+import org.lwjgl.opengl.GLUtil;
+import org.lwjgl.opengl.KHRDebug;
+import org.lwjgl.system.Callback;
+
+import com.badlogic.gdx.Application;
+import com.badlogic.gdx.ApplicationListener;
+import com.badlogic.gdx.Audio;
+import com.badlogic.gdx.Files;
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.Graphics;
+import com.badlogic.gdx.Input;
+import com.badlogic.gdx.LifecycleListener;
+import com.badlogic.gdx.Net;
+import com.badlogic.gdx.Preferences;
+import com.badlogic.gdx.backends.lwjgl3.audio.mock.MockAudio;
+import com.badlogic.gdx.utils.Array;
+import com.badlogic.gdx.utils.Clipboard;
+import com.badlogic.gdx.utils.GdxRuntimeException;
+import com.badlogic.gdx.utils.ObjectMap;
+import com.badlogic.gdx.utils.SharedLibraryLoader;
+import org.lwjgl.system.Configuration;
+
+/**
+ * This version of code is based on GDX 1.12.0 and was modified for the Terrarum project.
+ *
+ * Created by minjaesong on 2023-11-08.
+ */
+public class Lwjgl3Application implements Lwjgl3ApplicationBase {
+    private final Lwjgl3ApplicationConfiguration config;
+    final Array<Lwjgl3Window> windows = new Array<Lwjgl3Window>();
+    private volatile Lwjgl3Window currentWindow;
+    private Lwjgl3Audio audio;
+    private final Files files;
+    private final Net net;
+    private final ObjectMap<String, Preferences> preferences = new ObjectMap<String, Preferences>();
+    private final Lwjgl3Clipboard clipboard;
+    private int logLevel = LOG_INFO;
+    private ApplicationLogger applicationLogger;
+    private volatile boolean running = true;
+    private final Array<Runnable> runnables = new Array<Runnable>();
+    private final Array<Runnable> executedRunnables = new Array<Runnable>();
+    private final Array<LifecycleListener> lifecycleListeners = new Array<LifecycleListener>();
+    private static GLFWErrorCallback errorCallback;
+    private static GLVersion glVersion;
+    private static Callback glDebugCallback;
+    private final Sync sync;
+
+    static void initializeGlfw () {
+        if (errorCallback == null) {
+            if (SharedLibraryLoader.isMac) loadGlfwAwtMacos();
+            Lwjgl3NativesLoader.load();
+            errorCallback = GLFWErrorCallback.createPrint(Lwjgl3ApplicationConfiguration.errorStream);
+            GLFW.glfwSetErrorCallback(errorCallback);
+            if (SharedLibraryLoader.isMac) GLFW.glfwInitHint(GLFW.GLFW_ANGLE_PLATFORM_TYPE, GLFW.GLFW_ANGLE_PLATFORM_TYPE_METAL);
+            GLFW.glfwInitHint(GLFW.GLFW_JOYSTICK_HAT_BUTTONS, GLFW.GLFW_FALSE);
+            if (!GLFW.glfwInit()) {
+                throw new GdxRuntimeException("Unable to initialize GLFW");
+            }
+        }
+    }
+
+    static void loadANGLE () {
+        try {
+            Class angleLoader = Class.forName("com.badlogic.gdx.backends.lwjgl3.angle.ANGLELoader");
+            Method load = angleLoader.getMethod("load");
+            load.invoke(angleLoader);
+        } catch (ClassNotFoundException t) {
+            return;
+        } catch (Throwable t) {
+            throw new GdxRuntimeException("Couldn't load ANGLE.", t);
+        }
+    }
+
+    static void postLoadANGLE () {
+        try {
+            Class angleLoader = Class.forName("com.badlogic.gdx.backends.lwjgl3.angle.ANGLELoader");
+            Method load = angleLoader.getMethod("postGlfwInit");
+            load.invoke(angleLoader);
+        } catch (ClassNotFoundException t) {
+            return;
+        } catch (Throwable t) {
+            throw new GdxRuntimeException("Couldn't load ANGLE.", t);
+        }
+    }
+
+    static void loadGlfwAwtMacos () {
+        try {
+            Class loader = Class.forName("com.badlogic.gdx.backends.lwjgl3.awt.GlfwAWTLoader");
+            Method load = loader.getMethod("load");
+            File sharedLib = (File)load.invoke(loader);
+            Configuration.GLFW_LIBRARY_NAME.set(sharedLib.getAbsolutePath());
+            Configuration.GLFW_CHECK_THREAD0.set(false);
+        } catch (ClassNotFoundException t) {
+            return;
+        } catch (Throwable t) {
+            throw new GdxRuntimeException("Couldn't load GLFW AWT for macOS.", t);
+        }
+    }
+
+    public Lwjgl3Application (ApplicationListener listener) {
+        this(listener, new Lwjgl3ApplicationConfiguration());
+    }
+
+    public Lwjgl3Application (ApplicationListener listener, Lwjgl3ApplicationConfiguration config) {
+        if (config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20) loadANGLE();
+        initializeGlfw();
+        setApplicationLogger(new Lwjgl3ApplicationLogger());
+
+        this.config = config = Lwjgl3ApplicationConfiguration.copy(config);
+        if (config.title == null) config.title = listener.getClass().getSimpleName();
+
+        Gdx.app = this;
+        if (!config.disableAudio) {
+            try {
+                this.audio = createAudio(config);
+            } catch (Throwable t) {
+                log("Lwjgl3Application", "Couldn't initialize audio, disabling audio", t);
+                this.audio = new MockAudio();
+            }
+        } else {
+            this.audio = new MockAudio();
+        }
+        Gdx.audio = audio;
+        this.files = Gdx.files = createFiles();
+        this.net = Gdx.net = new Lwjgl3Net(config);
+        this.clipboard = new Lwjgl3Clipboard();
+
+        this.sync = new Sync();
+
+        Lwjgl3Window window = createWindow(config, listener, 0);
+        if (config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20) postLoadANGLE();
+        windows.add(window);
+        try {
+            loop();
+            cleanupWindows();
+        } catch (Throwable t) {
+            if (t instanceof RuntimeException)
+                throw (RuntimeException)t;
+            else
+                throw new GdxRuntimeException(t);
+        } finally {
+            cleanup();
+        }
+    }
+
+    protected void loop () {
+        Array<Lwjgl3Window> closedWindows = new Array<Lwjgl3Window>();
+        while (running && windows.size > 0) {
+//            System.out.println("aaaaaaaaaaaaaaaaaaaaa");
+
+//            audio.update(); // is handled on net.torvald.terrarum.AudioManager.update(float)
+
+            boolean haveWindowsRendered = false;
+            closedWindows.clear();
+            int targetFramerate = -2;
+            for (Lwjgl3Window window : windows) {
+                window.makeCurrent();
+                currentWindow = window;
+                if (targetFramerate == -2) targetFramerate = window.getConfig().foregroundFPS;
+                synchronized (lifecycleListeners) {
+                    haveWindowsRendered |= window.update();
+                }
+                if (window.shouldClose()) {
+                    closedWindows.add(window);
+                }
+            }
+            GLFW.glfwPollEvents();
+
+            boolean shouldRequestRendering;
+            synchronized (runnables) {
+                shouldRequestRendering = runnables.size > 0;
+                executedRunnables.clear();
+                executedRunnables.addAll(runnables);
+                runnables.clear();
+            }
+            for (Runnable runnable : executedRunnables) {
+                runnable.run();
+            }
+            if (shouldRequestRendering) {
+                // Must follow Runnables execution so changes done by Runnables are reflected
+                // in the following render.
+                for (Lwjgl3Window window : windows) {
+                    if (!window.getGraphics().isContinuousRendering()) window.requestRendering();
+                }
+            }
+
+            for (Lwjgl3Window closedWindow : closedWindows) {
+                if (windows.size == 1) {
+                    // Lifecycle listener methods have to be called before ApplicationListener methods. The
+                    // application will be disposed when _all_ windows have been disposed, which is the case,
+                    // when there is only 1 window left, which is in the process of being disposed.
+                    for (int i = lifecycleListeners.size - 1; i >= 0; i--) {
+                        LifecycleListener l = lifecycleListeners.get(i);
+                        l.pause();
+                        l.dispose();
+                    }
+                    lifecycleListeners.clear();
+                }
+                closedWindow.dispose();
+
+                windows.removeValue(closedWindow, false);
+            }
+
+            if (!haveWindowsRendered) {
+                // Sleep a few milliseconds in case no rendering was requested
+                // with continuous rendering disabled.
+                try {
+                    Thread.sleep(1000 / config.idleFPS);
+                } catch (InterruptedException e) {
+                    // ignore
+                }
+            } else if (targetFramerate > 0) {
+                sync.sync(targetFramerate); // sleep as needed to meet the target framerate
+            }
+        }
+    }
+
+    protected void cleanupWindows () {
+        synchronized (lifecycleListeners) {
+            for (LifecycleListener lifecycleListener : lifecycleListeners) {
+                lifecycleListener.pause();
+                lifecycleListener.dispose();
+            }
+        }
+        for (Lwjgl3Window window : windows) {
+            window.dispose();
+        }
+        windows.clear();
+    }
+
+    protected void cleanup () {
+        Lwjgl3Cursor.disposeSystemCursors();
+        audio.dispose();
+        errorCallback.free();
+        errorCallback = null;
+        if (glDebugCallback != null) {
+            glDebugCallback.free();
+            glDebugCallback = null;
+        }
+        GLFW.glfwTerminate();
+    }
+
+    @Override
+    public ApplicationListener getApplicationListener () {
+        return currentWindow.getListener();
+    }
+
+    @Override
+    public Graphics getGraphics () {
+        return currentWindow.getGraphics();
+    }
+
+    @Override
+    public Audio getAudio () {
+        return audio;
+    }
+
+    @Override
+    public Input getInput () {
+        return currentWindow.getInput();
+    }
+
+    @Override
+    public Files getFiles () {
+        return files;
+    }
+
+    @Override
+    public Net getNet () {
+        return net;
+    }
+
+    @Override
+    public void debug (String tag, String message) {
+        if (logLevel >= LOG_DEBUG) getApplicationLogger().debug(tag, message);
+    }
+
+    @Override
+    public void debug (String tag, String message, Throwable exception) {
+        if (logLevel >= LOG_DEBUG) getApplicationLogger().debug(tag, message, exception);
+    }
+
+    @Override
+    public void log (String tag, String message) {
+        if (logLevel >= LOG_INFO) getApplicationLogger().log(tag, message);
+    }
+
+    @Override
+    public void log (String tag, String message, Throwable exception) {
+        if (logLevel >= LOG_INFO) getApplicationLogger().log(tag, message, exception);
+    }
+
+    @Override
+    public void error (String tag, String message) {
+        if (logLevel >= LOG_ERROR) getApplicationLogger().error(tag, message);
+    }
+
+    @Override
+    public void error (String tag, String message, Throwable exception) {
+        if (logLevel >= LOG_ERROR) getApplicationLogger().error(tag, message, exception);
+    }
+
+    @Override
+    public void setLogLevel (int logLevel) {
+        this.logLevel = logLevel;
+    }
+
+    @Override
+    public int getLogLevel () {
+        return logLevel;
+    }
+
+    @Override
+    public void setApplicationLogger (ApplicationLogger applicationLogger) {
+        this.applicationLogger = applicationLogger;
+    }
+
+    @Override
+    public ApplicationLogger getApplicationLogger () {
+        return applicationLogger;
+    }
+
+    @Override
+    public ApplicationType getType () {
+        return ApplicationType.Desktop;
+    }
+
+    @Override
+    public int getVersion () {
+        return 0;
+    }
+
+    @Override
+    public long getJavaHeap () {
+        return Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory();
+    }
+
+    @Override
+    public long getNativeHeap () {
+        return getJavaHeap();
+    }
+
+    @Override
+    public Preferences getPreferences (String name) {
+        if (preferences.containsKey(name)) {
+            return preferences.get(name);
+        } else {
+            Preferences prefs = new Lwjgl3Preferences(
+                    new Lwjgl3FileHandle(new File(config.preferencesDirectory, name), config.preferencesFileType));
+            preferences.put(name, prefs);
+            return prefs;
+        }
+    }
+
+    @Override
+    public Clipboard getClipboard () {
+        return clipboard;
+    }
+
+    @Override
+    public void postRunnable (Runnable runnable) {
+        synchronized (runnables) {
+            runnables.add(runnable);
+        }
+    }
+
+    @Override
+    public void exit () {
+        running = false;
+    }
+
+    @Override
+    public void addLifecycleListener (LifecycleListener listener) {
+        synchronized (lifecycleListeners) {
+            lifecycleListeners.add(listener);
+        }
+    }
+
+    @Override
+    public void removeLifecycleListener (LifecycleListener listener) {
+        synchronized (lifecycleListeners) {
+            lifecycleListeners.removeValue(listener, true);
+        }
+    }
+
+    @Override
+    public Lwjgl3Audio createAudio (Lwjgl3ApplicationConfiguration config) {
+        return new OpenALLwjgl3Audio(config.audioDeviceSimultaneousSources, config.audioDeviceBufferCount,
+                config.audioDeviceBufferSize);
+    }
+
+    @Override
+    public Lwjgl3Input createInput (Lwjgl3Window window) {
+        return new DefaultLwjgl3Input(window);
+    }
+
+    protected Files createFiles () {
+        return new Lwjgl3Files();
+    }
+
+    /** Creates a new {@link Lwjgl3Window} using the provided listener and {@link Lwjgl3WindowConfiguration}.
+     *
+     * This function only just instantiates a {@link Lwjgl3Window} and returns immediately. The actual window creation is postponed
+     * with {@link Application#postRunnable(Runnable)} until after all existing windows are updated. */
+    public Lwjgl3Window newWindow (ApplicationListener listener, Lwjgl3WindowConfiguration config) {
+        Lwjgl3ApplicationConfiguration appConfig = Lwjgl3ApplicationConfiguration.copy(this.config);
+        appConfig.setWindowConfiguration(config);
+        if (appConfig.title == null) appConfig.title = listener.getClass().getSimpleName();
+        return createWindow(appConfig, listener, windows.get(0).getWindowHandle());
+    }
+
+    private Lwjgl3Window createWindow (final Lwjgl3ApplicationConfiguration config, ApplicationListener listener,
+                                       final long sharedContext) {
+        final Lwjgl3Window window = new Lwjgl3Window(listener, config, this);
+        if (sharedContext == 0) {
+            // the main window is created immediately
+            createWindow(window, config, sharedContext);
+        } else {
+            // creation of additional windows is deferred to avoid GL context trouble
+            postRunnable(new Runnable() {
+                public void run () {
+                    createWindow(window, config, sharedContext);
+                    windows.add(window);
+                }
+            });
+        }
+        return window;
+    }
+
+    void createWindow (Lwjgl3Window window, Lwjgl3ApplicationConfiguration config, long sharedContext) {
+        long windowHandle = createGlfwWindow(config, sharedContext);
+        window.create(windowHandle);
+        window.setVisible(config.initialVisible);
+
+        for (int i = 0; i < 2; i++) {
+            GL11.glClearColor(config.initialBackgroundColor.r, config.initialBackgroundColor.g, config.initialBackgroundColor.b,
+                    config.initialBackgroundColor.a);
+            GL11.glClear(GL11.GL_COLOR_BUFFER_BIT);
+            GLFW.glfwSwapBuffers(windowHandle);
+        }
+    }
+
+    static long createGlfwWindow (Lwjgl3ApplicationConfiguration config, long sharedContextWindow) {
+        GLFW.glfwDefaultWindowHints();
+        GLFW.glfwWindowHint(GLFW.GLFW_VISIBLE, GLFW.GLFW_FALSE);
+        GLFW.glfwWindowHint(GLFW.GLFW_RESIZABLE, config.windowResizable ? GLFW.GLFW_TRUE : GLFW.GLFW_FALSE);
+        GLFW.glfwWindowHint(GLFW.GLFW_MAXIMIZED, config.windowMaximized ? GLFW.GLFW_TRUE : GLFW.GLFW_FALSE);
+        GLFW.glfwWindowHint(GLFW.GLFW_AUTO_ICONIFY, config.autoIconify ? GLFW.GLFW_TRUE : GLFW.GLFW_FALSE);
+
+        GLFW.glfwWindowHint(GLFW.GLFW_RED_BITS, config.r);
+        GLFW.glfwWindowHint(GLFW.GLFW_GREEN_BITS, config.g);
+        GLFW.glfwWindowHint(GLFW.GLFW_BLUE_BITS, config.b);
+        GLFW.glfwWindowHint(GLFW.GLFW_ALPHA_BITS, config.a);
+        GLFW.glfwWindowHint(GLFW.GLFW_STENCIL_BITS, config.stencil);
+        GLFW.glfwWindowHint(GLFW.GLFW_DEPTH_BITS, config.depth);
+        GLFW.glfwWindowHint(GLFW.GLFW_SAMPLES, config.samples);
+
+        if (config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.GL30
+                || config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.GL31
+                || config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.GL32) {
+            GLFW.glfwWindowHint(GLFW.GLFW_CONTEXT_VERSION_MAJOR, config.gles30ContextMajorVersion);
+            GLFW.glfwWindowHint(GLFW.GLFW_CONTEXT_VERSION_MINOR, config.gles30ContextMinorVersion);
+            if (SharedLibraryLoader.isMac) {
+                // hints mandatory on OS X for GL 3.2+ context creation, but fail on Windows if the
+                // WGL_ARB_create_context extension is not available
+                // see: http://www.glfw.org/docs/latest/compat.html
+                GLFW.glfwWindowHint(GLFW.GLFW_OPENGL_FORWARD_COMPAT, GLFW.GLFW_TRUE);
+                GLFW.glfwWindowHint(GLFW.GLFW_OPENGL_PROFILE, GLFW.GLFW_OPENGL_CORE_PROFILE);
+            }
+        } else {
+            if (config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20) {
+                GLFW.glfwWindowHint(GLFW.GLFW_CONTEXT_CREATION_API, GLFW.GLFW_EGL_CONTEXT_API);
+                GLFW.glfwWindowHint(GLFW.GLFW_CLIENT_API, GLFW.GLFW_OPENGL_ES_API);
+                GLFW.glfwWindowHint(GLFW.GLFW_CONTEXT_VERSION_MAJOR, 2);
+                GLFW.glfwWindowHint(GLFW.GLFW_CONTEXT_VERSION_MINOR, 0);
+            }
+        }
+
+        if (config.transparentFramebuffer) {
+            GLFW.glfwWindowHint(GLFW.GLFW_TRANSPARENT_FRAMEBUFFER, GLFW.GLFW_TRUE);
+        }
+
+        if (config.debug) {
+            GLFW.glfwWindowHint(GLFW.GLFW_OPENGL_DEBUG_CONTEXT, GLFW.GLFW_TRUE);
+        }
+
+        long windowHandle = 0;
+
+        if (config.fullscreenMode != null) {
+            GLFW.glfwWindowHint(GLFW.GLFW_REFRESH_RATE, config.fullscreenMode.refreshRate);
+            windowHandle = GLFW.glfwCreateWindow(config.fullscreenMode.width, config.fullscreenMode.height, config.title,
+                    config.fullscreenMode.getMonitor(), sharedContextWindow);
+        } else {
+            GLFW.glfwWindowHint(GLFW.GLFW_DECORATED, config.windowDecorated ? GLFW.GLFW_TRUE : GLFW.GLFW_FALSE);
+            windowHandle = GLFW.glfwCreateWindow(config.windowWidth, config.windowHeight, config.title, 0, sharedContextWindow);
+        }
+        if (windowHandle == 0) {
+            throw new GdxRuntimeException("Couldn't create window");
+        }
+        Lwjgl3Window.setSizeLimits(windowHandle, config.windowMinWidth, config.windowMinHeight, config.windowMaxWidth,
+                config.windowMaxHeight);
+        if (config.fullscreenMode == null) {
+            if (config.windowX == -1 && config.windowY == -1) {
+                int windowWidth = Math.max(config.windowWidth, config.windowMinWidth);
+                int windowHeight = Math.max(config.windowHeight, config.windowMinHeight);
+                if (config.windowMaxWidth > -1) windowWidth = Math.min(windowWidth, config.windowMaxWidth);
+                if (config.windowMaxHeight > -1) windowHeight = Math.min(windowHeight, config.windowMaxHeight);
+
+                long monitorHandle = GLFW.glfwGetPrimaryMonitor();
+                if (config.windowMaximized && config.maximizedMonitor != null) {
+                    monitorHandle = config.maximizedMonitor.monitorHandle;
+                }
+
+                IntBuffer areaXPos = BufferUtils.createIntBuffer(1);
+                IntBuffer areaYPos = BufferUtils.createIntBuffer(1);
+                IntBuffer areaWidth = BufferUtils.createIntBuffer(1);
+                IntBuffer areaHeight = BufferUtils.createIntBuffer(1);
+                GLFW.glfwGetMonitorWorkarea(monitorHandle, areaXPos, areaYPos, areaWidth, areaHeight);
+
+                GLFW.glfwSetWindowPos(windowHandle, Math.max(0, areaXPos.get(0) + areaWidth.get(0) / 2 - windowWidth / 2),
+                        Math.max(0, areaYPos.get(0) + areaHeight.get(0) / 2 - windowHeight / 2));
+            } else {
+                GLFW.glfwSetWindowPos(windowHandle, config.windowX, config.windowY);
+            }
+
+            if (config.windowMaximized) {
+                GLFW.glfwMaximizeWindow(windowHandle);
+            }
+        }
+        if (config.windowIconPaths != null) {
+            Lwjgl3Window.setIcon(windowHandle, config.windowIconPaths, config.windowIconFileType);
+        }
+        GLFW.glfwMakeContextCurrent(windowHandle);
+        GLFW.glfwSwapInterval(config.vSyncEnabled ? 1 : 0);
+        if (config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20) {
+            try {
+                Class gles = Class.forName("org.lwjgl.opengles.GLES");
+                gles.getMethod("createCapabilities").invoke(gles);
+            } catch (Throwable e) {
+                throw new GdxRuntimeException("Couldn't initialize GLES", e);
+            }
+        } else {
+            GL.createCapabilities();
+        }
+
+        initiateGL(config.glEmulation == Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20);
+        if (!glVersion.isVersionEqualToOrHigher(2, 0))
+            throw new GdxRuntimeException("OpenGL 2.0 or higher with the FBO extension is required. OpenGL version: "
+                    + GL11.glGetString(GL11.GL_VERSION) + "\n" + glVersion.getDebugVersionString());
+
+        if (config.glEmulation != Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20 && !supportsFBO()) {
+            throw new GdxRuntimeException("OpenGL 2.0 or higher with the FBO extension is required. OpenGL version: "
+                    + GL11.glGetString(GL11.GL_VERSION) + ", FBO extension: false\n" + glVersion.getDebugVersionString());
+        }
+
+        if (config.debug) {
+            glDebugCallback = GLUtil.setupDebugMessageCallback(config.debugStream);
+            setGLDebugMessageControl(GLDebugMessageSeverity.NOTIFICATION, false);
+        }
+
+        return windowHandle;
+    }
+
+    private static void initiateGL (boolean useGLES20) {
+        if (!useGLES20) {
+            String versionString = GL11.glGetString(GL11.GL_VERSION);
+            String vendorString = GL11.glGetString(GL11.GL_VENDOR);
+            String rendererString = GL11.glGetString(GL11.GL_RENDERER);
+            glVersion = new GLVersion(Application.ApplicationType.Desktop, versionString, vendorString, rendererString);
+        } else {
+            try {
+                Class gles = Class.forName("org.lwjgl.opengles.GLES20");
+                Method getString = gles.getMethod("glGetString", int.class);
+                String versionString = (String)getString.invoke(gles, GL11.GL_VERSION);
+                String vendorString = (String)getString.invoke(gles, GL11.GL_VENDOR);
+                String rendererString = (String)getString.invoke(gles, GL11.GL_RENDERER);
+                glVersion = new GLVersion(Application.ApplicationType.Desktop, versionString, vendorString, rendererString);
+            } catch (Throwable e) {
+                throw new GdxRuntimeException("Couldn't get GLES version string.", e);
+            }
+        }
+    }
+
+    private static boolean supportsFBO () {
+        // FBO is in core since OpenGL 3.0, see https://www.opengl.org/wiki/Framebuffer_Object
+        return glVersion.isVersionEqualToOrHigher(3, 0) || GLFW.glfwExtensionSupported("GL_EXT_framebuffer_object")
+                || GLFW.glfwExtensionSupported("GL_ARB_framebuffer_object");
+    }
+
+    public enum GLDebugMessageSeverity {
+        HIGH(GL43.GL_DEBUG_SEVERITY_HIGH, KHRDebug.GL_DEBUG_SEVERITY_HIGH, ARBDebugOutput.GL_DEBUG_SEVERITY_HIGH_ARB,
+                AMDDebugOutput.GL_DEBUG_SEVERITY_HIGH_AMD), MEDIUM(GL43.GL_DEBUG_SEVERITY_MEDIUM, KHRDebug.GL_DEBUG_SEVERITY_MEDIUM,
+                ARBDebugOutput.GL_DEBUG_SEVERITY_MEDIUM_ARB, AMDDebugOutput.GL_DEBUG_SEVERITY_MEDIUM_AMD), LOW(
+                GL43.GL_DEBUG_SEVERITY_LOW, KHRDebug.GL_DEBUG_SEVERITY_LOW, ARBDebugOutput.GL_DEBUG_SEVERITY_LOW_ARB,
+                AMDDebugOutput.GL_DEBUG_SEVERITY_LOW_AMD), NOTIFICATION(GL43.GL_DEBUG_SEVERITY_NOTIFICATION,
+                KHRDebug.GL_DEBUG_SEVERITY_NOTIFICATION, -1, -1);
+
+        final int gl43, khr, arb, amd;
+
+        GLDebugMessageSeverity (int gl43, int khr, int arb, int amd) {
+            this.gl43 = gl43;
+            this.khr = khr;
+            this.arb = arb;
+            this.amd = amd;
+        }
+    }
+
+    /** Enables or disables GL debug messages for the specified severity level. Returns false if the severity level could not be
+     * set (e.g. the NOTIFICATION level is not supported by the ARB and AMD extensions).
+     *
+     * See {@link Lwjgl3ApplicationConfiguration#enableGLDebugOutput(boolean, PrintStream)} */
+    public static boolean setGLDebugMessageControl (GLDebugMessageSeverity severity, boolean enabled) {
+        GLCapabilities caps = GL.getCapabilities();
+        final int GL_DONT_CARE = 0x1100; // not defined anywhere yet
+
+        if (caps.OpenGL43) {
+            GL43.glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, severity.gl43, (IntBuffer)null, enabled);
+            return true;
+        }
+
+        if (caps.GL_KHR_debug) {
+            KHRDebug.glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, severity.khr, (IntBuffer)null, enabled);
+            return true;
+        }
+
+        if (caps.GL_ARB_debug_output && severity.arb != -1) {
+            ARBDebugOutput.glDebugMessageControlARB(GL_DONT_CARE, GL_DONT_CARE, severity.arb, (IntBuffer)null, enabled);
+            return true;
+        }
+
+        if (caps.GL_AMD_debug_output && severity.amd != -1) {
+            AMDDebugOutput.glDebugMessageEnableAMD(GL_DONT_CARE, severity.amd, (IntBuffer)null, enabled);
+            return true;
+        }
+
+        return false;
+    }
+
+}
diff --git a/src/net/torvald/terrarum/App.java b/src/net/torvald/terrarum/App.java
index a67007669..6d651fe7a 100644
--- a/src/net/torvald/terrarum/App.java
+++ b/src/net/torvald/terrarum/App.java
@@ -74,6 +74,11 @@ public class App implements ApplicationListener {
                 (VERSION_TAG.isBlank() ? "" : "-"+VERSION_TAG) + (snap == null ? "" : (" (" + snap + ")"));
     }
 
+    public static final String getVERSION_STRING_WITHOUT_SNAPSHOT() {
+        return String.format("%d.%d.%d", VERSION_RAW >>> 48, (VERSION_RAW & 0xffff000000L) >>> 24, VERSION_RAW & 0xffffffL) +
+                (VERSION_TAG.isBlank() ? "" : "-"+VERSION_TAG);
+    }
+
     /**
      * when FALSE, some assertion and print code will not execute
      */
@@ -1182,7 +1187,6 @@ public class App implements ApplicationListener {
 
         AudioManager.INSTANCE.getMasterVolume();
         audioManagerThread = new Thread(new AudioManagerRunnable(), "TerrarumAudioManager");
-        audioManagerThread.setPriority(2);
         audioManagerThread.start();
 
         Terrarum.initialise();
diff --git a/src/net/torvald/terrarum/AudioManager.kt b/src/net/torvald/terrarum/AudioManager.kt
index 5c95e8784..c29e9f212 100644
--- a/src/net/torvald/terrarum/AudioManager.kt
+++ b/src/net/torvald/terrarum/AudioManager.kt
@@ -1,12 +1,17 @@
 package net.torvald.terrarum
 
+import com.badlogic.gdx.Gdx
+import com.badlogic.gdx.backends.lwjgl3.audio.Lwjgl3Audio
 import net.torvald.terrarum.App.printdbg
 import net.torvald.terrarum.modulebasegame.MusicContainer
 
 /**
+ * Any audio reference fed into this manager will get lost; you must manually store and dispose of them on your own.
+ *
  * Created by minjaesong on 2023-11-07.
  */
 object AudioManager {
+    const val DEFAULT_FADEOUT_LEN = 2.4f
 
     /** Returns a master volume */
     val masterVolume: Float
@@ -27,25 +32,28 @@ object AudioManager {
     private var nextMusic: MusicContainer? = null
 
     private var fadeAkku = 0f
-    private var fadeLength = 1f
+    private var fadeLength = DEFAULT_FADEOUT_LEN
 
     private var fadeoutFired = false
     private var fadeinFired = false
 
     fun update(delta: Float) {
+        (Gdx.audio as? Lwjgl3Audio)?.update()
+
+
         if (fadeoutFired) {
             fadeAkku += delta
-            currentMusic?.gdxMusic?.volume = musicVolume * (1f - (fadeAkku / fadeLength)).coerceIn(0f, 1f)
+            currentMusic?.gdxMusic?.volume = (musicVolume * (1f - (fadeAkku / fadeLength))).coerceIn(0f, 1f)
 
-            printdbg(this, "Fadeout fired - akku: $fadeAkku; volume: ${currentMusic?.gdxMusic?.volume}")
+//            printdbg(this, "Fadeout fired - akku: $fadeAkku; volume: ${currentMusic?.gdxMusic?.volume}")
 
             if (fadeAkku >= fadeLength) {
                 fadeoutFired = false
                 currentMusic?.gdxMusic?.volume = 0f
-                currentMusic?.gdxMusic?.pause()
+//                currentMusic?.gdxMusic?.pause()
                 currentMusic = null
 
-                printdbg(this, "Fadeout end")
+//                printdbg(this, "Fadeout end")
             }
         }
         // process fadein request
@@ -53,24 +61,24 @@ object AudioManager {
             fadeAkku += delta
             currentMusic?.gdxMusic?.volume = (musicVolume * (fadeAkku / fadeLength)).coerceIn(0f, 1f)
 
-            printdbg(this, "Fadein fired - akku: $fadeAkku; volume: ${currentMusic?.gdxMusic?.volume}")
+//            printdbg(this, "Fadein fired - akku: $fadeAkku; volume: ${currentMusic?.gdxMusic?.volume}")
 
             if (currentMusic?.gdxMusic?.isPlaying == false) {
                 currentMusic?.gdxMusic?.play()
-                printdbg(this, "Fadein starting music ${currentMusic?.name}")
+//                printdbg(this, "Fadein starting music ${currentMusic?.name}")
             }
 
             if (fadeAkku >= fadeLength) {
                 currentMusic?.gdxMusic?.volume = musicVolume
                 fadeinFired = false
 
-                printdbg(this, "Fadein end")
+//                printdbg(this, "Fadein end")
             }
         }
 
 
         if (currentMusic?.gdxMusic?.isPlaying != true && nextMusic != null) {
-            printdbg(this, "Playing next music: ${nextMusic!!.name}")
+//            printdbg(this, "Playing next music: ${nextMusic!!.name}")
             currentMusic = nextMusic
             nextMusic = null
             currentMusic!!.gdxMusic.volume = musicVolume
@@ -80,13 +88,13 @@ object AudioManager {
 
     fun startMusic(song: MusicContainer) {
         if (currentMusic?.gdxMusic?.isPlaying == true) {
-            requestFadeOut(1f)
+            requestFadeOut(DEFAULT_FADEOUT_LEN)
         }
         nextMusic = song
     }
 
     fun stopMusic() {
-        requestFadeOut(1f)
+        requestFadeOut(DEFAULT_FADEOUT_LEN)
     }
 
     fun requestFadeOut(length: Float) {
diff --git a/src/net/torvald/terrarum/AudioManagerRunnable.kt b/src/net/torvald/terrarum/AudioManagerRunnable.kt
index 11a2f97ab..f881172ea 100644
--- a/src/net/torvald/terrarum/AudioManagerRunnable.kt
+++ b/src/net/torvald/terrarum/AudioManagerRunnable.kt
@@ -18,7 +18,8 @@ class AudioManagerRunnable : Runnable {
                 dT = (T - oldT) / 1000000000f
                 oldT = T;
                 AudioManager.update(dT)
-                Thread.sleep(20L)
+//                println("AudioManagerRunnable dT = ${dT * 1000f} ms")
+                Thread.sleep(30L)
             }
             catch (e: InterruptedException) {
                 break
diff --git a/src/net/torvald/terrarum/CheckUpdate.kt b/src/net/torvald/terrarum/CheckUpdate.kt
index f6aabc37b..86eba7604 100644
--- a/src/net/torvald/terrarum/CheckUpdate.kt
+++ b/src/net/torvald/terrarum/CheckUpdate.kt
@@ -17,7 +17,7 @@ import java.net.http.HttpResponse
  */
 object CheckUpdate {
 
-    private val versionNumFull = App.getVERSION_STRING()
+    private val versionNumFull = App.getVERSION_STRING_WITHOUT_SNAPSHOT()
     private val versionNumOnly = String.format(
         "%d.%d.%d",
         App.VERSION_RAW ushr 48,
diff --git a/src/net/torvald/terrarum/SavegameCollection.kt b/src/net/torvald/terrarum/SavegameCollection.kt
index a070cd48e..f0effda41 100644
--- a/src/net/torvald/terrarum/SavegameCollection.kt
+++ b/src/net/torvald/terrarum/SavegameCollection.kt
@@ -40,7 +40,7 @@ class SavegameCollection(files0: List<DiskSkimmer>, prefiltered: Boolean) {
     val manualSaves = files.filter { !it.diskFile.extension.matches(Regex("[a-z]")) }
 
     init {
-        printdbg(this, "Rebuilding skimmers (${files.size})")
+//        printdbg(this, "Rebuilding skimmers (${files.size})")
 //        files.forEach { it.rebuild() }
     }
 
diff --git a/src/net/torvald/terrarum/Terrarum.kt b/src/net/torvald/terrarum/Terrarum.kt
index d96ed6cec..b53213499 100644
--- a/src/net/torvald/terrarum/Terrarum.kt
+++ b/src/net/torvald/terrarum/Terrarum.kt
@@ -794,7 +794,7 @@ fun AppUpdateListOfSavegames() {
 
 
     // create list of worlds
-    printdbg("ListSavegames", "Listing saved worlds...")
+//    printdbg("ListSavegames", "Listing saved worlds...")
     val worldsDirLs = File(worldsDir).listFiles().filter { !it.isDirectory && !it.name.contains('.') }.mapNotNull { file ->
         try {
             DiskSkimmer(file, true)
@@ -820,16 +820,16 @@ fun AppUpdateListOfSavegames() {
     }
     filteringResults.forEachIndexed { index, list ->
         val it = list.first()
-        printdbg("ListSavegames", " ${index+1}.\t${it.diskFile.absolutePath}")
+//        printdbg("ListSavegames", " ${index+1}.\t${it.diskFile.absolutePath}")
 
-        printdbg("ListSavegames", "    collecting...")
+//        printdbg("ListSavegames", "    collecting...")
         val collection = SavegameCollection.collectFromBaseFilename(list, it.diskFile.name)
-        printdbg("ListSavegames", "    disk rebuilding...")
+//        printdbg("ListSavegames", "    disk rebuilding...")
         collection.rebuildLoadable()
-        printdbg("ListSavegames", "    get UUID...")
+//        printdbg("ListSavegames", "    get UUID...")
         val worldUUID = collection.getUUID()
 
-        printdbg("ListSavegames", "    registration...")
+//        printdbg("ListSavegames", "    registration...")
         // if multiple valid savegames with same UUID exist, only the most recent one is retained
         if (!App.savegameWorlds.contains(worldUUID)) {
             App.savegameWorlds[worldUUID] = collection
@@ -840,7 +840,7 @@ fun AppUpdateListOfSavegames() {
 
 
     // create list of players
-    printdbg("ListSavegames", "Listing saved players...")
+//    printdbg("ListSavegames", "Listing saved players...")
     val playersDirLs = File(playersDir).listFiles().filter { !it.isDirectory && !it.name.contains('.') }.mapNotNull { file ->
         try {
             DiskSkimmer(file, true)
@@ -866,16 +866,16 @@ fun AppUpdateListOfSavegames() {
     }
     filteringResults2.forEachIndexed { index, list ->
         val it = list.first()
-        printdbg("ListSavegames", " ${index+1}.\t${it.diskFile.absolutePath}")
+//        printdbg("ListSavegames", " ${index+1}.\t${it.diskFile.absolutePath}")
 
-        printdbg("ListSavegames", "    collecting...")
+//        printdbg("ListSavegames", "    collecting...")
         val collection = SavegameCollection.collectFromBaseFilename(list, it.diskFile.name)
-        printdbg("ListSavegames", "    disk rebuilding...")
+//        printdbg("ListSavegames", "    disk rebuilding...")
         collection.rebuildLoadable()
-        printdbg("ListSavegames", "    get UUID...")
+//        printdbg("ListSavegames", "    get UUID...")
         val playerUUID = collection.getUUID()
 
-        printdbg("ListSavegames", "    registration...")
+//        printdbg("ListSavegames", "    registration...")
         // if multiple valid savegames with same UUID exist, only the most recent one is retained
         if (!App.savegamePlayers.contains(playerUUID)) {
             App.savegamePlayers[playerUUID] = collection
diff --git a/src/net/torvald/terrarum/modulebasegame/TerrarumMusicGovernor.kt b/src/net/torvald/terrarum/modulebasegame/TerrarumMusicGovernor.kt
index 0137f35c1..421966a01 100644
--- a/src/net/torvald/terrarum/modulebasegame/TerrarumMusicGovernor.kt
+++ b/src/net/torvald/terrarum/modulebasegame/TerrarumMusicGovernor.kt
@@ -25,7 +25,11 @@ class TerrarumMusicGovernor : MusicGovernor() {
                 MusicContainer(
                     it.nameWithoutExtension.replace('_', ' ').split(" ").map { it.capitalize() }.joinToString(" "),
                     it,
-                    Gdx.audio.newMusic(Gdx.files.absolute(it.absolutePath))
+                    Gdx.audio.newMusic(Gdx.files.absolute(it.absolutePath)).also {
+                        it.setOnCompletionListener {
+                            stopMusic()
+                        }
+                    }
                 )
             }
             catch (e: GdxRuntimeException) {
@@ -98,9 +102,7 @@ class TerrarumMusicGovernor : MusicGovernor() {
                 }
             }
             STATE_PLAYING -> {
-                if (AudioManager.currentMusic?.gdxMusic?.isPlaying == false) {
-//                    stopMusic()
-                }
+                // stopMusic() will be called when the music finishes; it's on the setOnCompletionListener
             }
             STATE_INTERMISSION -> {
                 intermissionAkku += delta