Fix macOS Swift warnings

macos/Sources/Features/Command Palette/CommandPalette.swift

@@ -136,7 +136,7 @@ struct CommandPaletteView: View {
                     break
                 }
             }
-            .onChange(of: query) { newValue in
+            .backport.onChange(of: query) { newValue in
                 // If the user types a query then we want to make sure the first
                 // value is selected. If the user clears the query and we were selecting
                 // the first, we unset any selection.
@@ -181,7 +181,7 @@ struct CommandPaletteView: View {
         .shadow(radius: 32, x: 0, y: 12)
         .padding()
         .environment(\.colorScheme, scheme)
-        .onChange(of: isPresented) { newValue in
+        .backport.onChange(of: isPresented) { newValue in
             if !newValue {
                 // This is optional, since most of the time
                 // there will be a delay before the next use.
@@ -261,7 +261,7 @@ private struct CommandPaletteQuery: View {
                 .frame(height: 48)
                 .textFieldStyle(.plain)
                 .focused($isTextFieldFocused)
-                .onChange(of: isTextFieldFocused) { focused in
+                .backport.onChange(of: isTextFieldFocused) { focused in
                     if !focused {
                         onEvent?(.exit)
                     }
@@ -322,7 +322,7 @@ private struct CommandTable: View {
                     .padding(10)
                 }
                 .frame(maxHeight: 200)
-                .onChange(of: selectedIndex) { _ in
+                .backport.onChange(of: selectedIndex) {
                     guard let selectedIndex,
                           selectedIndex < options.count else { return }
                     proxy.scrollTo(

macos/Sources/Features/Command Palette/TerminalCommandPalette.swift

@@ -41,7 +41,7 @@ struct TerminalCommandPaletteView: View {
                 }
             }
         }
-        .onChange(of: isPresented) { newValue in
+        .backport.onChange(of: isPresented) { newValue in
             // When the command palette disappears we need to send focus back to the
             // surface view we were overlaid on top of. There's probably a better way
             // to handle the first responder state here but I don't know it.

macos/Sources/Features/Terminal/TerminalView.swift

@@ -86,7 +86,7 @@ struct TerminalView<ViewModel: TerminalViewModel>: View {
                         .ghosttyLastFocusedSurface(lastFocusedSurface)
                         .focused($focused)
                         .onAppear { self.focused = true }
-                        .onChange(of: focusedSurface) { newValue in
+                        .backport.onChange(of: focusedSurface) { newValue in
                             // We want to keep track of our last focused surface so even if
                             // we lose focus we keep this set to the last non-nil value.
                             if newValue != nil {
@@ -94,10 +94,10 @@ struct TerminalView<ViewModel: TerminalViewModel>: View {
                                 self.delegate?.focusedSurfaceDidChange(to: newValue)
                             }
                         }
-                        .onChange(of: pwdURL) { newValue in
+                        .backport.onChange(of: pwdURL) { newValue in
                             self.delegate?.pwdDidChange(to: newValue)
                         }
-                        .onChange(of: cellSize) { newValue in
+                        .backport.onChange(of: cellSize) { newValue in
                             guard let size = newValue else { return }
                             self.delegate?.cellSizeDidChange(to: size)
                         }

macos/Sources/Features/Update/UpdatePill.swift

@@ -21,7 +21,7 @@ struct UpdatePill: View {
                     UpdatePopoverView(model: model)
                 }
                 .transition(.opacity.combined(with: .scale(scale: 0.95)))
-                .onChange(of: model.state) { newState in
+                .backport.onChange(of: model.state) { newState in
                     resetTask?.cancel()
                     if case .notFound(let notFound) = newState {
                         resetTask = Task { [weak model] in

macos/Sources/Ghostty/Ghostty.Inspector.swift

@@ -5,7 +5,7 @@ extension Ghostty {
     /// Represents the inspector for a surface within Ghostty.
     ///
     /// Wraps a `ghostty_inspector_t`
-    final class Inspector: Sendable {
+    final class Inspector: @unchecked Sendable {
         private let inspector: ghostty_inspector_t
 
         /// Read the underlying C value for this inspector. This is unsafe because the value will be

macos/Sources/Ghostty/Ghostty.Surface.swift

@@ -9,7 +9,7 @@ extension Ghostty {
     /// all over.
     ///
     /// Wraps a `ghostty_surface_t`
-    final class Surface: Sendable {
+    final class Surface: @unchecked Sendable {
         private let surface: ghostty_surface_t
 
         /// Read the underlying C value for this surface. This is unsafe because the value will be

macos/Sources/Ghostty/GhosttyPackage.swift

@@ -7,10 +7,6 @@ import GhosttyKit
 /// A command is fully self-contained so it is Sendable.
 extension ghostty_command_s: @unchecked @retroactive Sendable {}
 
-/// A surface is sendable because it is just a reference type. Using the surface in parameters
-/// may be unsafe but the value itself is safe to send across threads.
-extension ghostty_surface_t: @unchecked @retroactive Sendable {}
-
 extension Ghostty {
     // The user notification category identifier
     static let userNotificationCategory = "com.mitchellh.ghostty.userNotification"

macos/Sources/Ghostty/Surface View/InspectorView.swift

@@ -39,7 +39,7 @@ extension Ghostty {
                 }
             }
             .onReceive(pubInspector) { onControlInspector($0) }
-            .onChange(of: surfaceView.inspectorVisible) { inspectorVisible in
+            .backport.onChange(of: surfaceView.inspectorVisible) { inspectorVisible in
                 // When we show the inspector, we want to focus on the inspector.
                 // When we hide the inspector, we want to move focus back to the surface.
                 if inspectorVisible {

macos/Sources/Ghostty/Surface View/SurfaceView.swift

@@ -937,7 +937,7 @@ extension Ghostty {
                                 .opacity(dotOpacity(for: index))
                         }
                     }
-                    .onChange(of: context.date.timeIntervalSinceReferenceDate) { newValue in
+                    .backport.onChange(of: context.date.timeIntervalSinceReferenceDate) { newValue in
                         animationPhase = newValue
                     }
                 }
@@ -1011,7 +1011,7 @@ extension Ghostty {
             .allowsHitTesting(false)
             .opacity(highlighted ? 1.0 : 0.0)
             .animation(.easeOut(duration: 0.4), value: highlighted)
-            .onChange(of: highlighted) { newValue in
+            .backport.onChange(of: highlighted) { newValue in
                 if newValue {
                     withAnimation(.easeInOut(duration: 0.4).repeatForever(autoreverses: true)) {
                         borderPulse = true

macos/Sources/Ghostty/Surface View/SurfaceView_AppKit.swift

@@ -1726,27 +1726,31 @@ extension Ghostty {
                 trigger: nil
             )
 
-            // Note the callback may be executed on a background thread as documented
-            // so we need @MainActor since we're reading/writing view state.
-            UNUserNotificationCenter.current().add(request) { @MainActor error in
+            // Note the callback may be executed on a background thread as documented,
+            // so view state is updated from an explicit main-actor task below.
+            UNUserNotificationCenter.current().add(request) { [weak self, uuid] error in
                 if let error = error {
                     AppDelegate.logger.error("Error scheduling user notification: \(error)")
                     return
                 }
 
-                // We need to keep track of this notification so we can remove it
-                // under certain circumstances
-                self.notificationIdentifiers.insert(uuid)
+                Task { @MainActor [weak self, uuid] in
+                    guard let self else { return }
 
-                // If we're focused then we schedule to remove the notification
-                // after a few seconds. If we gain focus we automatically remove it
-                // in focusDidChange.
-                if self.focused {
-                    Task { @MainActor [weak self] in
-                        try await Task.sleep(for: .seconds(3))
-                        self?.notificationIdentifiers.remove(uuid)
-                        UNUserNotificationCenter.current()
-                            .removeDeliveredNotifications(withIdentifiers: [uuid])
+                    // We need to keep track of this notification so we can remove it
+                    // under certain circumstances.
+                    self.notificationIdentifiers.insert(uuid)
+
+                    // If we're focused then we schedule to remove the notification
+                    // after a few seconds. If we gain focus we automatically remove it
+                    // in focusDidChange.
+                    if self.focused {
+                        Task { @MainActor [weak self, uuid] in
+                            try await Task.sleep(for: .seconds(3))
+                            self?.notificationIdentifiers.remove(uuid)
+                            UNUserNotificationCenter.current()
+                                .removeDeliveredNotifications(withIdentifiers: [uuid])
+                        }
                     }
                 }
             }

macos/Sources/Helpers/Backport.swift

@@ -25,6 +25,39 @@ enum BackportKeyPressResult {
 }
 
 extension Backport where Content: View {
+    /// Backported onChange that uses the modern two-parameter closure on
+    /// platforms that provide it while preserving macOS 13 support.
+    func onChange<Value: Equatable>(
+        of value: Value,
+        _ action: @escaping (Value) -> Void
+    ) -> some View {
+        if #available(iOS 17, macOS 14, *) {
+            return content.onChange(of: value) { _, newValue in
+                action(newValue)
+            }
+        } else {
+            return content.onChange(of: value) { newValue in
+                action(newValue)
+            }
+        }
+    }
+
+    /// Backported onChange variant for handlers that do not need the new value.
+    func onChange<Value: Equatable>(
+        of value: Value,
+        _ action: @escaping () -> Void
+    ) -> some View {
+        if #available(iOS 17, macOS 14, *) {
+            return content.onChange(of: value) { _, _ in
+                action()
+            }
+        } else {
+            return content.onChange(of: value) { _ in
+                action()
+            }
+        }
+    }
+
     func pointerVisibility(_ v: BackportVisibility) -> some View {
         #if canImport(AppKit)
         if #available(macOS 15, *) {

macos/Sources/Helpers/Extensions/KeyboardShortcut+Extension.swift

@@ -47,6 +47,8 @@ extension KeyboardShortcut: @retroactive CustomStringConvertible {
 }
 
 // This is available in macOS 14 so this only applies to early macOS versions.
+@available(macOS, introduced: 10.15, obsoleted: 14.0)
+@available(iOS, introduced: 13.0, obsoleted: 17.0)
 extension KeyEquivalent: @retroactive Equatable {
     public static func == (lhs: KeyEquivalent, rhs: KeyEquivalent) -> Bool {
         lhs.character == rhs.character