diff --git a/portprotonqt/app.py b/portprotonqt/app.py
index 38a580d..5be0984 100644
--- a/portprotonqt/app.py
+++ b/portprotonqt/app.py
@@ -1,11 +1,17 @@
 import sys
 import os
 import subprocess
-from PySide6.QtCore import QLocale, QTranslator, QLibraryInfo
+from PySide6.QtCore import QLocale, QTranslator, QLibraryInfo, QTimer, Qt
 from PySide6.QtWidgets import QApplication
 from PySide6.QtGui import QIcon
+from PySide6.QtNetwork import QLocalServer, QLocalSocket
+
 from portprotonqt.main_window import MainWindow
-from portprotonqt.config_utils import save_fullscreen_config, get_portproton_location
+from portprotonqt.config_utils import (
+    save_fullscreen_config,
+    read_fullscreen_config,
+    get_portproton_location,
+)
 from portprotonqt.logger import get_logger, setup_logger
 from portprotonqt.cli import parse_args
 
@@ -13,28 +19,29 @@ __app_id__ = "ru.linux_gaming.PortProtonQt"
 __app_name__ = "PortProtonQt"
 __app_version__ = "0.1.8"
 
+
 def get_version():
     try:
         commit = subprocess.check_output(
-            ['git', 'rev-parse', '--short', 'HEAD'],
-            stderr=subprocess.DEVNULL
-        ).decode('utf-8').strip()
+            ["git", "rev-parse", "--short", "HEAD"],
+            stderr=subprocess.DEVNULL,
+        ).decode("utf-8").strip()
         return f"{__app_version__} ({commit})"
     except (subprocess.CalledProcessError, FileNotFoundError, OSError):
         return __app_version__
 
+
 def main():
-    os.environ['PW_CLI'] = '1'
-    os.environ['PROCESS_LOG'] = '1'
-    os.environ['START_FROM_STEAM'] = '1'
+    os.environ["PW_CLI"] = "1"
+    os.environ["PROCESS_LOG"] = "1"
+    os.environ["START_FROM_STEAM"] = "1"
 
     portproton_path = get_portproton_location()
-
     if portproton_path is None:
         return
 
-    script_path = os.path.join(portproton_path, 'data', 'scripts', 'start.sh')
-    subprocess.run([script_path, 'cli', '--initial'])
+    script_path = os.path.join(portproton_path, "data", "scripts", "start.sh")
+    subprocess.run([script_path, "cli", "--initial"])
 
     app = QApplication(sys.argv)
     app.setWindowIcon(QIcon.fromTheme(__app_id__))
@@ -43,41 +50,117 @@ def main():
     app.setApplicationVersion(__app_version__)
 
     args = parse_args()
-
-    # Setup logger with specified debug level
     setup_logger(args.debug_level)
-
-    # Reinitialize logger after setup to ensure it uses the new configuration
     logger = get_logger(__name__)
 
+    # --- Single-instance logic ---
+    server_name = __app_id__
+    socket = QLocalSocket()
+    socket.connectToServer(server_name)
+
+    if socket.waitForConnected(200):
+        # Второй экземпляр — передаём команду первому
+        fullscreen = args.fullscreen or read_fullscreen_config()
+        msg = b"show:fullscreen" if fullscreen else b"show"
+        socket.write(msg)
+        socket.flush()
+        socket.waitForBytesWritten(500)
+        socket.disconnectFromServer()
+        logger.info("Restored existing instance from tray")
+        return
+
+    # Если старый сокет остался — удалить
+    QLocalServer.removeServer(server_name)
+
+    local_server = QLocalServer()
+    if not local_server.listen(server_name):
+        logger.warning(f"Failed to start local server: {local_server.errorString()}")
+        return
+
+    # --- Qt translations ---
     system_locale = QLocale.system()
     qt_translator = QTranslator()
     translations_path = QLibraryInfo.path(QLibraryInfo.LibraryPath.TranslationsPath)
     if qt_translator.load(system_locale, "qtbase", "_", translations_path):
         app.installTranslator(qt_translator)
     else:
-        logger.warning(f"Qt translations for {system_locale.name()} not found in {translations_path}, using english language")
+        logger.warning(
+            f"Qt translations for {system_locale.name()} not found in {translations_path}, using English"
+        )
 
+    # --- Main Window ---
     version = get_version()
     window = MainWindow(app_name=__app_name__, version=version)
 
-    if args.fullscreen:
-        logger.info("Launching in fullscreen mode due to --fullscreen flag")
+    # --- Handle incoming connections ---
+    def handle_new_connection():
+        conn = local_server.nextPendingConnection()
+        if not conn:
+            return
+
+        if conn.waitForReadyRead(1000):
+            data = conn.readAll().data()
+            msg = bytes(data).decode("utf-8", errors="ignore")
+            logger.info(f"IPC message received: {msg}")
+
+            def restore_window():
+                try:
+                    if msg.startswith("show"):
+                        if hasattr(window, "restore_from_tray"):
+                            window.restore_from_tray()  # type: ignore[attr-defined]
+                        else:
+                            window.showNormal()
+                            window.raise_()
+                            window.activateWindow()
+                            window.setWindowState(
+                                window.windowState() & ~Qt.WindowState.WindowMinimized | Qt.WindowState.WindowActive
+                            )
+
+                        if ":fullscreen" in msg:
+                            logger.info("Switching to fullscreen via IPC")
+                            save_fullscreen_config(True)
+                            window.showFullScreen()
+                        else:
+                            logger.info("Switching to normal window via IPC")
+                            save_fullscreen_config(False)
+                            window.showNormal()
+                except Exception as e:
+                    logger.warning(f"Failed to restore window: {e}")
+
+            # Выполняем в основном потоке
+            QTimer.singleShot(0, restore_window)
+
+        conn.disconnectFromServer()
+
+    local_server.newConnection.connect(handle_new_connection)
+
+    # --- Initial fullscreen state ---
+    launch_fullscreen = args.fullscreen or read_fullscreen_config()
+    if launch_fullscreen:
+        logger.info(
+            f"Launching in fullscreen mode ({'--fullscreen' if args.fullscreen else 'config'})"
+        )
         save_fullscreen_config(True)
         window.showFullScreen()
+    else:
+        logger.info("Launching in normal mode")
+        save_fullscreen_config(False)
+        window.showNormal()
 
+    # --- Cleanup ---
     def cleanup_on_exit():
-        nonlocal window
-        app.aboutToQuit.disconnect()
-        if window:
-            window.close()
-        app.quit()
+        try:
+            local_server.close()
+            QLocalServer.removeServer(server_name)
+            if window:
+                window.close()
+        except Exception as e:
+            logger.warning(f"Cleanup error: {e}")
 
     app.aboutToQuit.connect(cleanup_on_exit)
 
-    window.show()
-
     sys.exit(app.exec())
 
-if __name__ == '__main__':
+
+if __name__ == "__main__":
     main()