diff --git a/Packages/vChewing_CocoaExtension/Sources/CocoaExtension/CocoaExtension_Misc.swift b/Packages/vChewing_CocoaExtension/Sources/CocoaExtension/CocoaExtension_Misc.swift
index e65be034..bd0921d1 100644
--- a/Packages/vChewing_CocoaExtension/Sources/CocoaExtension/CocoaExtension_Misc.swift
+++ b/Packages/vChewing_CocoaExtension/Sources/CocoaExtension/CocoaExtension_Misc.swift
@@ -50,7 +50,7 @@ extension NSApplication {
   public static var isDarkMode: Bool {
     if #unavailable(macOS 10.14) { return false }
     if #available(macOS 10.15, *) {
-      let appearanceDescription = NSApplication.shared.effectiveAppearance.debugDescription
+      let appearanceDescription = NSApp.effectiveAppearance.debugDescription
         .lowercased()
       return appearanceDescription.contains("dark")
     } else if let appleInterfaceStyle = UserDefaults.standard.string(forKey: "AppleInterfaceStyle") {
diff --git a/Packages/vChewing_Uninstaller/Sources/Uninstaller/Uninstaller.swift b/Packages/vChewing_Uninstaller/Sources/Uninstaller/Uninstaller.swift
index 5d4222ef..cfcb909b 100644
--- a/Packages/vChewing_Uninstaller/Sources/Uninstaller/Uninstaller.swift
+++ b/Packages/vChewing_Uninstaller/Sources/Uninstaller/Uninstaller.swift
@@ -67,7 +67,7 @@ public enum Uninstaller {
     if !FileManager.trashTargetIfExists(pathIMELibrary + kTargetBundle) { return -1 }  // 最後移除 App 自身
     // 幹掉殘留在記憶體內的執行緒。
     if selfKill {
-      NSApplication.shared.terminate(nil)
+      NSApp.terminate(nil)
     }
     return 0
   }
diff --git a/Source/Modules/AppDelegate.swift b/Source/Modules/AppDelegate.swift
index 09e2fb05..640d5fc1 100644
--- a/Source/Modules/AppDelegate.swift
+++ b/Source/Modules/AppDelegate.swift
@@ -114,6 +114,6 @@ class AppDelegate: NSObject, NSApplicationDelegate, NSUserNotificationCenterDele
   // New About Window
   @IBAction func about(_: Any) {
     CtlAboutWindow.show()
-    NSApplication.shared.activate(ignoringOtherApps: true)
+    NSApp.activate(ignoringOtherApps: true)
   }
 }
diff --git a/Source/Modules/UIModules/PrefUI/VwrPrefPaneDevZone.swift b/Source/Modules/UIModules/PrefUI/VwrPrefPaneDevZone.swift
index 77af68bf..8a6823ed 100644
--- a/Source/Modules/UIModules/PrefUI/VwrPrefPaneDevZone.swift
+++ b/Source/Modules/UIModules/PrefUI/VwrPrefPaneDevZone.swift
@@ -55,7 +55,7 @@ struct VwrPrefPaneDevZone: View {
             isOn: $selUseIMKCandidateWindow.onChange {
               PrefMgr.shared.useIMKCandidateWindow = selUseIMKCandidateWindow
               NSLog("vChewing App self-terminated due to enabling / disabling IMK candidate window.")
-              NSApplication.shared.terminate(nil)
+              NSApp.terminate(nil)
             }
           )
           Text(
diff --git a/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift b/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift
index ebe067cf..910d817d 100644
--- a/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift
+++ b/Source/Modules/UIModules/PrefUI/VwrPrefPaneDictionary.swift
@@ -88,7 +88,7 @@ struct VwrPrefPaneDictionary: View {
                       PrefMgr.shared.userDataFolderSpecified = newPath
                       tbxUserDataPathSpecified = PrefMgr.shared.userDataFolderSpecified
                       BookmarkManager.shared.saveBookmark(for: url)
-                      (NSApplication.shared.delegate as! AppDelegate).updateDirectoryMonitorPath()
+                      (NSApp.delegate as! AppDelegate).updateDirectoryMonitorPath()
                     } else {
                       IMEApp.buzz()
                       if !bolPreviousFolderValidity {
diff --git a/Source/Modules/UIModules/PrefUI/VwrPrefPaneGeneral.swift b/Source/Modules/UIModules/PrefUI/VwrPrefPaneGeneral.swift
index 190a52f2..57e749f0 100644
--- a/Source/Modules/UIModules/PrefUI/VwrPrefPaneGeneral.swift
+++ b/Source/Modules/UIModules/PrefUI/VwrPrefPaneGeneral.swift
@@ -99,7 +99,7 @@ struct VwrPrefPaneGeneral: View {
                 UserDefaults.standard.removeObject(forKey: UserDef.kAppleLanguages.rawValue)
               }
               NSLog("vChewing App self-terminated due to UI language change.")
-              NSApplication.shared.terminate(nil)
+              NSApp.terminate(nil)
             }
           ) {
             Text(LocalizedStringKey("Follow OS settings")).tag(["auto"])
diff --git a/Source/Modules/WindowControllers/CtlPrefWindow.swift b/Source/Modules/WindowControllers/CtlPrefWindow.swift
index 42d50916..fa398b7a 100644
--- a/Source/Modules/WindowControllers/CtlPrefWindow.swift
+++ b/Source/Modules/WindowControllers/CtlPrefWindow.swift
@@ -194,13 +194,13 @@ class CtlPrefWindow: NSWindowController {
       }
 
       NSLog("vChewing App self-terminated due to UI language change.")
-      NSApplication.shared.terminate(nil)
+      NSApp.terminate(nil)
     }
   }
 
   @IBAction func updateIMKCandidateEnableStatusAction(_: Any) {
     NSLog("vChewing App self-terminated due to enabling / disabling IMK candidate window.")
-    NSApplication.shared.terminate(nil)
+    NSApp.terminate(nil)
   }
 
   @IBAction func clickedWhetherIMEShouldNotFartToggleAction(_: Any) {
@@ -260,7 +260,7 @@ class CtlPrefWindow: NSWindowController {
         if LMMgr.checkIfSpecifiedUserDataFolderValid(newPath) {
           PrefMgr.shared.userDataFolderSpecified = newPath
           BookmarkManager.shared.saveBookmark(for: url)
-          (NSApplication.shared.delegate as! AppDelegate).updateDirectoryMonitorPath()
+          (NSApp.delegate as! AppDelegate).updateDirectoryMonitorPath()
         } else {
           IMEApp.buzz()
           if !bolPreviousFolderValidity {
diff --git a/UserPhraseEditor/AppDelegate.swift b/UserPhraseEditor/AppDelegate.swift
index f0cefbc3..188c7b7f 100644
--- a/UserPhraseEditor/AppDelegate.swift
+++ b/UserPhraseEditor/AppDelegate.swift
@@ -25,6 +25,6 @@ class AppDelegate: NSObject, NSApplicationDelegate {
   // Call the New About Window
   @IBAction func about(_: Any) {
     CtlAboutWindow.show()
-    NSApplication.shared.activate(ignoringOtherApps: true)
+    NSApp.activate(ignoringOtherApps: true)
   }
 }