feat: reduce memory usage by storing fewer app icons

src/logic/Application.swift

@@ -81,13 +81,6 @@ class Application: NSObject {
         executableURL = runningApplication.executableURL
         debugId = "(pid:\(pid) \(bundleIdentifier ?? bundleURL?.absoluteString ?? executableURL?.absoluteString ?? localizedName))"
         super.init()
-        BackgroundWork.screenshotsQueue.addOperation { [weak self] in
-            guard let self else { return }
-            let r = Application.appIconWithoutPadding(runningApplication.icon)
-            DispatchQueue.main.async { [weak self] in
-                self?.icon = r
-            }
-        }
         Logger.info { self.debugId }
         observeEventsIfEligible()
         kvObservers = [
@@ -122,6 +115,17 @@ class Application: NSObject {
         }
     }
 
+    func fetchAppIcon() {
+        guard icon == nil else { return }
+        BackgroundWork.screenshotsQueue.addOperation { [weak self] in
+            guard let self, self.icon == nil else { return }
+            let r = Application.appIconWithoutPadding(runningApplication.icon)
+            DispatchQueue.main.async { [weak self] in
+                self?.icon = r
+            }
+        }
+    }
+
     private func observeEvents() {
         guard let axObserver else { return }
         AXUIElement.retryAxCallUntilTimeout(context: debugId, pid: pid, callType: .subscribeToAppNotification) { [weak self] in

src/logic/Window.swift

@@ -55,6 +55,8 @@ class Window {
         // the app may have timed out trying to subscribe to app notifications
         // It may be responsive now since it has a window; we attempt again
         application.observeEventsIfEligible()
+        // fetch app icon only if we display that app in the switcher
+        application.fetchAppIcon()
         checkIfFocused()
         Logger.info { self.debugId }
         observeEvents()
@@ -67,6 +69,8 @@ class Window {
         Window.globalCreationCounter += 1
         creationOrder = Window.globalCreationCounter
         debugId = "\(application.debugId) (title:\(title))"
+        // fetch app icon only if we display that app in the switcher
+        application.fetchAppIcon()
         Logger.debug { self.debugId }
     }