diff --git a/Source/Modules/AppDelegate.swift b/Source/Modules/AppDelegate.swift
index 1f754516..96779163 100644
--- a/Source/Modules/AppDelegate.swift
+++ b/Source/Modules/AppDelegate.swift
@@ -15,6 +15,7 @@ import UpdateSputnik
 
 @objc(AppDelegate)
 public class AppDelegate: NSObject, NSApplicationDelegate, NSUserNotificationCenterDelegate {
+  public static let shared = AppDelegate()
   private var folderMonitor = FolderMonitor(
     url: URL(fileURLWithPath: LMMgr.dataFolderPath(isDefaultFolder: false))
   )
diff --git a/Source/Modules/SessionCtl_Core.swift b/Source/Modules/SessionCtl_Core.swift
index 95635d1b..48305e53 100644
--- a/Source/Modules/SessionCtl_Core.swift
+++ b/Source/Modules/SessionCtl_Core.swift
@@ -292,7 +292,7 @@ public extension SessionCtl {
 
       DispatchQueue.main.async {
         UpdateSputnik.shared.checkForUpdate(forced: false, url: kUpdateInfoSourceURL)
-        (NSApp.delegate as? AppDelegate)?.checkMemoryUsage()
+        AppDelegate.shared.checkMemoryUsage()
       }
 
       state = IMEState.ofEmpty()
diff --git a/Source/Modules/SessionCtl_Menu.swift b/Source/Modules/SessionCtl_Menu.swift
index 120da837..8765a9e7 100644
--- a/Source/Modules/SessionCtl_Menu.swift
+++ b/Source/Modules/SessionCtl_Menu.swift
@@ -363,7 +363,7 @@ public extension SessionCtl {
   }
 
   @objc func selfUninstall(_: Any? = nil) {
-    (NSApp.delegate as? AppDelegate)?.selfUninstall()
+    AppDelegate.shared.selfUninstall()
   }
 
   @objc func selfTerminate(_: Any? = nil) {
diff --git a/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift b/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift
index 51050616..4f03c3a1 100644
--- a/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift
+++ b/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift
@@ -86,7 +86,7 @@ struct VwrPrefPaneDictionary: View {
                       if LMMgr.checkIfSpecifiedUserDataFolderValid(newPath) {
                         userDataFolderSpecified = newPath
                         BookmarkManager.shared.saveBookmark(for: url)
-                        (NSApp.delegate as? AppDelegate)?.updateDirectoryMonitorPath()
+                        AppDelegate.shared.updateDirectoryMonitorPath()
                       } else {
                         IMEApp.buzz()
                         if !bolPreviousFolderValidity {
diff --git a/Source/Modules/WindowControllers/CtlPrefWindow.swift b/Source/Modules/WindowControllers/CtlPrefWindow.swift
index a7693e01..4e1d9a10 100644
--- a/Source/Modules/WindowControllers/CtlPrefWindow.swift
+++ b/Source/Modules/WindowControllers/CtlPrefWindow.swift
@@ -354,7 +354,7 @@ class CtlPrefWindow: NSWindowController, NSWindowDelegate {
         if LMMgr.checkIfSpecifiedUserDataFolderValid(newPath) {
           PrefMgr.shared.userDataFolderSpecified = newPath
           BookmarkManager.shared.saveBookmark(for: url)
-          (NSApp.delegate as? AppDelegate)?.updateDirectoryMonitorPath()
+          AppDelegate.shared.updateDirectoryMonitorPath()
         } else {
           IMEApp.buzz()
           if !bolPreviousFolderValidity {
diff --git a/Source/Modules/main.swift b/Source/Modules/main.swift
index 60a36a66..8afc7b52 100644
--- a/Source/Modules/main.swift
+++ b/Source/Modules/main.swift
@@ -67,7 +67,8 @@ else {
 public let theServer = server
 public let kUpdateInfoSourceURL = urlUpdateInfoSource
 
-NSApp.run()
+NSApplication.shared.delegate = AppDelegate.shared
+_ = NSApplicationMain(CommandLine.argc, CommandLine.unsafeArgv)
 
 // MARK: - Top-level Enums relating to Input Mode and Language Supports.