feat: avoid occasional delays in showing the switcher (closes #5109)

src/ui/App.swift

@@ -220,7 +220,6 @@ class App: AppCenterApplication {
         Logger.debug(shortcutIndex, self.shortcutIndex, isFirstSummon)
         App.app.appIsBeingUsed = true
         if isFirstSummon || shortcutIndex != self.shortcutIndex {
-            MainMenu.toggle(enabled: false)
             NSScreen.updatePreferred()
             if isVeryFirstSummon {
                 Windows.sortByLevel()

src/ui/MainMenu.swift

@@ -1,5 +1,6 @@
 class MainMenu {
     private static var mainMenu: NSMenu!
+    private static var menuItemsWithShortcut = [NSMenuItem: String]()
 
     /// classic keyboard shortcuts like copy-and-paste are missing without a MainMenu. We generated the default menu from XCode and load it
     /// see https://stackoverflow.com/a/3746058/2249756
@@ -8,16 +9,26 @@ class MainMenu {
         Bundle.main.loadNibNamed("MainMenu", owner: self, topLevelObjects: &menuObjects)
         mainMenu = menuObjects?.first { $0 is NSMenu } as? NSMenu
         App.shared.mainMenu = mainMenu
+        rememberMenuItemsWithShortcut()
     }
 
-    /// we toggle the mainMenu off when showing the main window, and on when showing secondary windows
     static func toggle(enabled: Bool) {
-        if enabled {
-            if App.shared.mainMenu == nil {
-                App.shared.mainMenu = mainMenu
+        for (item, keyEquivalent) in menuItemsWithShortcut {
+            item.keyEquivalent = enabled ? keyEquivalent : ""
+        }
+    }
+
+    private static func rememberMenuItemsWithShortcut() {
+        var stack: [NSMenu] = [mainMenu]
+        while let menu = stack.popLast() {
+            for item in menu.items {
+                if !item.keyEquivalent.isEmpty {
+                    menuItemsWithShortcut[item] = item.keyEquivalent
+                }
+                if let submenu = item.submenu {
+                    stack.append(submenu)
+                }
             }
-        } else {
-            App.shared.mainMenu = nil
         }
     }
 }

src/ui/main-window/ThumbnailsPanel.swift

@@ -99,6 +99,15 @@ extension ThumbnailsPanel: NSWindowDelegate {
             if App.app.appIsBeingUsed {
                 App.app.thumbnailsPanel.makeKeyAndOrderFront(nil)
             }
+            MainMenu.toggle(enabled: true)
+        }
+    }
+
+    func windowDidBecomeKey(_ notification: Notification) {
+        // we toggle the mainMenu off when showing the main window
+        // this avoids command+q from quitting AltTab itself, or command+p from printing
+        DispatchQueue.main.async {
+            MainMenu.toggle(enabled: false)
         }
     }
 }