Merge pull request #2762 from ghostty-org/config-update

apprt config change notification, macOS transparent titlebar works with theme change

include/ghostty.h

@@ -532,6 +532,11 @@ typedef struct {
   uint8_t b;
 } ghostty_action_color_change_s;
 
+// apprt.action.ConfigChange
+typedef struct {
+  ghostty_config_t config;
+} ghostty_action_config_change_s;
+
 // apprt.Action.Key
 typedef enum {
   GHOSTTY_ACTION_NEW_WINDOW,
@@ -568,6 +573,7 @@ typedef enum {
   GHOSTTY_ACTION_KEY_SEQUENCE,
   GHOSTTY_ACTION_COLOR_CHANGE,
   GHOSTTY_ACTION_CONFIG_CHANGE_CONDITIONAL_STATE,
+  GHOSTTY_ACTION_CONFIG_CHANGE,
 } ghostty_action_tag_e;
 
 typedef union {
@@ -592,6 +598,7 @@ typedef union {
   ghostty_action_secure_input_e secure_input;
   ghostty_action_key_sequence_s key_sequence;
   ghostty_action_color_change_s color_change;
+  ghostty_action_config_change_s config_change;
 } ghostty_action_u;
 
 typedef struct {
@@ -639,6 +646,7 @@ ghostty_info_s ghostty_info(void);
 
 ghostty_config_t ghostty_config_new();
 void ghostty_config_free(ghostty_config_t);
+ghostty_config_t ghostty_config_clone(ghostty_config_t);
 void ghostty_config_load_cli_args(ghostty_config_t);
 void ghostty_config_load_default_files(ghostty_config_t);
 void ghostty_config_load_recursive_files(ghostty_config_t);

macos/Sources/App/macOS/AppDelegate.swift

@@ -69,6 +69,9 @@ class AppDelegate: NSObject,
     /// seconds since the process was launched.
     private var applicationLaunchTime: TimeInterval = 0
 
+    /// This is the current configuration from the Ghostty configuration that we need.
+    private var derivedConfig: DerivedConfig = DerivedConfig()
+
     /// The ghostty global state. Only one per process.
     let ghostty: Ghostty.App = Ghostty.App()
 
@@ -138,7 +141,7 @@ class AppDelegate: NSObject,
         menuCheckForUpdates?.action = #selector(SPUStandardUpdaterController.checkForUpdates(_:))
 
         // Initial config loading
-        configDidReload(ghostty)
+        ghosttyConfigDidChange(config: ghostty.config)
 
         // Start our update checker.
         updaterController.startUpdater()
@@ -162,6 +165,12 @@ class AppDelegate: NSObject,
             name: .quickTerminalDidChangeVisibility,
             object: nil
         )
+        NotificationCenter.default.addObserver(
+            self,
+            selector: #selector(ghosttyConfigDidChange(_:)),
+            name: .ghosttyConfigDidChange,
+            object: nil
+        )
 
         // Configure user notifications
         let actions = [
@@ -188,13 +197,13 @@ class AppDelegate: NSObject,
         // is possible to have other windows in a few scenarios:
         //   - if we're opening a URL since `application(_:openFile:)` is called before this.
         //   - if we're restoring from persisted state
-        if terminalManager.windows.count == 0 && ghostty.config.initialWindow {
+        if terminalManager.windows.count == 0 && derivedConfig.initialWindow {
             terminalManager.newWindow()
         }
     }
 
     func applicationShouldTerminateAfterLastWindowClosed(_ sender: NSApplication) -> Bool {
-        return ghostty.config.shouldQuitAfterLastWindowClosed
+        return derivedConfig.shouldQuitAfterLastWindowClosed
     }
 
     func applicationShouldTerminate(_ sender: NSApplication) -> NSApplication.TerminateReply {
@@ -300,52 +309,52 @@ class AppDelegate: NSObject,
     }
 
     /// Sync all of our menu item keyboard shortcuts with the Ghostty configuration.
-    private func syncMenuShortcuts() {
+    private func syncMenuShortcuts(_ config: Ghostty.Config) {
         guard ghostty.readiness == .ready else { return }
 
-        syncMenuShortcut(action: "open_config", menuItem: self.menuOpenConfig)
+        syncMenuShortcut(config, action: "open_config", menuItem: self.menuOpenConfig)
-        syncMenuShortcut(action: "reload_config", menuItem: self.menuReloadConfig)
+        syncMenuShortcut(config, action: "reload_config", menuItem: self.menuReloadConfig)
-        syncMenuShortcut(action: "quit", menuItem: self.menuQuit)
+        syncMenuShortcut(config, action: "quit", menuItem: self.menuQuit)
 
-        syncMenuShortcut(action: "new_window", menuItem: self.menuNewWindow)
+        syncMenuShortcut(config, action: "new_window", menuItem: self.menuNewWindow)
-        syncMenuShortcut(action: "new_tab", menuItem: self.menuNewTab)
+        syncMenuShortcut(config, action: "new_tab", menuItem: self.menuNewTab)
-        syncMenuShortcut(action: "close_surface", menuItem: self.menuClose)
+        syncMenuShortcut(config, action: "close_surface", menuItem: self.menuClose)
-        syncMenuShortcut(action: "close_window", menuItem: self.menuCloseWindow)
+        syncMenuShortcut(config, action: "close_window", menuItem: self.menuCloseWindow)
-        syncMenuShortcut(action: "close_all_windows", menuItem: self.menuCloseAllWindows)
+        syncMenuShortcut(config, action: "close_all_windows", menuItem: self.menuCloseAllWindows)
-        syncMenuShortcut(action: "new_split:right", menuItem: self.menuSplitRight)
+        syncMenuShortcut(config, action: "new_split:right", menuItem: self.menuSplitRight)
-        syncMenuShortcut(action: "new_split:down", menuItem: self.menuSplitDown)
+        syncMenuShortcut(config, action: "new_split:down", menuItem: self.menuSplitDown)
 
-        syncMenuShortcut(action: "copy_to_clipboard", menuItem: self.menuCopy)
+        syncMenuShortcut(config, action: "copy_to_clipboard", menuItem: self.menuCopy)
-        syncMenuShortcut(action: "paste_from_clipboard", menuItem: self.menuPaste)
+        syncMenuShortcut(config, action: "paste_from_clipboard", menuItem: self.menuPaste)
-        syncMenuShortcut(action: "select_all", menuItem: self.menuSelectAll)
+        syncMenuShortcut(config, action: "select_all", menuItem: self.menuSelectAll)
 
-        syncMenuShortcut(action: "toggle_split_zoom", menuItem: self.menuZoomSplit)
+        syncMenuShortcut(config, action: "toggle_split_zoom", menuItem: self.menuZoomSplit)
-        syncMenuShortcut(action: "goto_split:previous", menuItem: self.menuPreviousSplit)
+        syncMenuShortcut(config, action: "goto_split:previous", menuItem: self.menuPreviousSplit)
-        syncMenuShortcut(action: "goto_split:next", menuItem: self.menuNextSplit)
+        syncMenuShortcut(config, action: "goto_split:next", menuItem: self.menuNextSplit)
-        syncMenuShortcut(action: "goto_split:top", menuItem: self.menuSelectSplitAbove)
+        syncMenuShortcut(config, action: "goto_split:top", menuItem: self.menuSelectSplitAbove)
-        syncMenuShortcut(action: "goto_split:bottom", menuItem: self.menuSelectSplitBelow)
+        syncMenuShortcut(config, action: "goto_split:bottom", menuItem: self.menuSelectSplitBelow)
-        syncMenuShortcut(action: "goto_split:left", menuItem: self.menuSelectSplitLeft)
+        syncMenuShortcut(config, action: "goto_split:left", menuItem: self.menuSelectSplitLeft)
-        syncMenuShortcut(action: "goto_split:right", menuItem: self.menuSelectSplitRight)
+        syncMenuShortcut(config, action: "goto_split:right", menuItem: self.menuSelectSplitRight)
-        syncMenuShortcut(action: "resize_split:up,10", menuItem: self.menuMoveSplitDividerUp)
+        syncMenuShortcut(config, action: "resize_split:up,10", menuItem: self.menuMoveSplitDividerUp)
-        syncMenuShortcut(action: "resize_split:down,10", menuItem: self.menuMoveSplitDividerDown)
+        syncMenuShortcut(config, action: "resize_split:down,10", menuItem: self.menuMoveSplitDividerDown)
-        syncMenuShortcut(action: "resize_split:right,10", menuItem: self.menuMoveSplitDividerRight)
+        syncMenuShortcut(config, action: "resize_split:right,10", menuItem: self.menuMoveSplitDividerRight)
-        syncMenuShortcut(action: "resize_split:left,10", menuItem: self.menuMoveSplitDividerLeft)
+        syncMenuShortcut(config, action: "resize_split:left,10", menuItem: self.menuMoveSplitDividerLeft)
-        syncMenuShortcut(action: "equalize_splits", menuItem: self.menuEqualizeSplits)
+        syncMenuShortcut(config, action: "equalize_splits", menuItem: self.menuEqualizeSplits)
 
-        syncMenuShortcut(action: "increase_font_size:1", menuItem: self.menuIncreaseFontSize)
+        syncMenuShortcut(config, action: "increase_font_size:1", menuItem: self.menuIncreaseFontSize)
-        syncMenuShortcut(action: "decrease_font_size:1", menuItem: self.menuDecreaseFontSize)
+        syncMenuShortcut(config, action: "decrease_font_size:1", menuItem: self.menuDecreaseFontSize)
-        syncMenuShortcut(action: "reset_font_size", menuItem: self.menuResetFontSize)
+        syncMenuShortcut(config, action: "reset_font_size", menuItem: self.menuResetFontSize)
-        syncMenuShortcut(action: "toggle_quick_terminal", menuItem: self.menuQuickTerminal)
+        syncMenuShortcut(config, action: "toggle_quick_terminal", menuItem: self.menuQuickTerminal)
-        syncMenuShortcut(action: "toggle_visibility", menuItem: self.menuToggleVisibility)
+        syncMenuShortcut(config, action: "toggle_visibility", menuItem: self.menuToggleVisibility)
-        syncMenuShortcut(action: "inspector:toggle", menuItem: self.menuTerminalInspector)
+        syncMenuShortcut(config, action: "inspector:toggle", menuItem: self.menuTerminalInspector)
 
-        syncMenuShortcut(action: "toggle_secure_input", menuItem: self.menuSecureInput)
+        syncMenuShortcut(config, action: "toggle_secure_input", menuItem: self.menuSecureInput)
 
         // This menu item is NOT synced with the configuration because it disables macOS
         // global fullscreen keyboard shortcut. The shortcut in the Ghostty config will continue
         // to work but it won't be reflected in the menu item.
         //
-        // syncMenuShortcut(action: "toggle_fullscreen", menuItem: self.menuToggleFullScreen)
+        // syncMenuShortcut(config, action: "toggle_fullscreen", menuItem: self.menuToggleFullScreen)
 
         // Dock menu
         reloadDockMenu()
@@ -353,9 +362,9 @@ class AppDelegate: NSObject,
 
     /// Syncs a single menu shortcut for the given action. The action string is the same
     /// action string used for the Ghostty configuration.
-    private func syncMenuShortcut(action: String, menuItem: NSMenuItem?) {
+    private func syncMenuShortcut(_ config: Ghostty.Config, action: String, menuItem: NSMenuItem?) {
         guard let menu = menuItem else { return }
-        guard let equiv = ghostty.config.keyEquivalent(for: action) else {
+        guard let equiv = config.keyEquivalent(for: action) else {
             // No shortcut, clear the menu item
             menu.keyEquivalent = ""
             menu.keyEquivalentModifierMask = []
@@ -422,6 +431,98 @@ class AppDelegate: NSObject,
         self.menuQuickTerminal?.state = if (quickController.visible) { .on } else { .off }
     }
 
+    @objc private func ghosttyConfigDidChange(_ notification: Notification) {
+        // We only care if the configuration is a global configuration, not a surface one.
+        guard notification.object == nil else { return }
+
+        // Get our managed configuration object out
+        guard let config = notification.userInfo?[
+            Notification.Name.GhosttyConfigChangeKey
+        ] as? Ghostty.Config else { return }
+
+        ghosttyConfigDidChange(config: config)
+    }
+
+    private func ghosttyConfigDidChange(config: Ghostty.Config) {
+        // Update the config we need to store
+        self.derivedConfig = DerivedConfig(config)
+
+        // Depending on the "window-save-state" setting we have to set the NSQuitAlwaysKeepsWindows
+        // configuration. This is the only way to carefully control whether macOS invokes the
+        // state restoration system.
+        switch (config.windowSaveState) {
+        case "never": UserDefaults.standard.setValue(false, forKey: "NSQuitAlwaysKeepsWindows")
+        case "always": UserDefaults.standard.setValue(true, forKey: "NSQuitAlwaysKeepsWindows")
+        case "default": fallthrough
+        default: UserDefaults.standard.removeObject(forKey: "NSQuitAlwaysKeepsWindows")
+        }
+
+        // Sync our auto-update settings
+        updaterController.updater.automaticallyChecksForUpdates =
+            config.autoUpdate == .check || config.autoUpdate == .download
+        updaterController.updater.automaticallyDownloadsUpdates =
+            config.autoUpdate == .download
+
+        // Config could change keybindings, so update everything that depends on that
+        syncMenuShortcuts(config)
+        terminalManager.relabelAllTabs()
+
+        // Config could change window appearance. We wrap this in an async queue because when
+        // this is called as part of application launch it can deadlock with an internal
+        // AppKit mutex on the appearance.
+        DispatchQueue.main.async { self.syncAppearance(config: config) }
+
+        // If we have configuration errors, we need to show them.
+        let c = ConfigurationErrorsController.sharedInstance
+        c.errors = config.errors
+        if (c.errors.count > 0) {
+            if (c.window == nil || !c.window!.isVisible) {
+                c.showWindow(self)
+            }
+        }
+
+        // We need to handle our global event tap depending on if there are global
+        // events that we care about in Ghostty.
+        if (ghostty_app_has_global_keybinds(ghostty.app!)) {
+            if (timeSinceLaunch > 5) {
+                // If the process has been running for awhile we enable right away
+                // because no windows are likely to pop up.
+                GlobalEventTap.shared.enable()
+            } else {
+                // If the process just started, we wait a couple seconds to allow
+                // the initial windows and so on to load so our permissions dialog
+                // doesn't get buried.
+                DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(2)) {
+                    GlobalEventTap.shared.enable()
+                }
+            }
+        } else {
+            GlobalEventTap.shared.disable()
+        }
+    }
+
+    /// Sync the appearance of our app with the theme specified in the config.
+    private func syncAppearance(config: Ghostty.Config) {
+        guard let theme = config.windowTheme else { return }
+        switch (theme) {
+        case "dark":
+            let appearance = NSAppearance(named: .darkAqua)
+            NSApplication.shared.appearance = appearance
+
+        case "light":
+            let appearance = NSAppearance(named: .aqua)
+            NSApplication.shared.appearance = appearance
+
+        case "auto":
+            let color = OSColor(config.backgroundColor)
+            let appearance = NSAppearance(named: color.isLightColor ? .aqua : .darkAqua)
+            NSApplication.shared.appearance = appearance
+
+        default:
+            NSApplication.shared.appearance = nil
+        }
+    }
+
     //MARK: - Restorable State
 
     /// We support NSSecureCoding for restorable state. Required as of macOS Sonoma (14) but a good idea anyways.
@@ -470,88 +571,6 @@ class AppDelegate: NSObject,
         return nil
     }
 
-    func configDidReload(_ state: Ghostty.App) {
-        // Depending on the "window-save-state" setting we have to set the NSQuitAlwaysKeepsWindows
-        // configuration. This is the only way to carefully control whether macOS invokes the
-        // state restoration system.
-        switch (ghostty.config.windowSaveState) {
-        case "never": UserDefaults.standard.setValue(false, forKey: "NSQuitAlwaysKeepsWindows")
-        case "always": UserDefaults.standard.setValue(true, forKey: "NSQuitAlwaysKeepsWindows")
-        case "default": fallthrough
-        default: UserDefaults.standard.removeObject(forKey: "NSQuitAlwaysKeepsWindows")
-        }
-
-        // Sync our auto-update settings
-        updaterController.updater.automaticallyChecksForUpdates =
-            ghostty.config.autoUpdate == .check || ghostty.config.autoUpdate == .download
-        updaterController.updater.automaticallyDownloadsUpdates =
-            ghostty.config.autoUpdate == .download
-
-        // Config could change keybindings, so update everything that depends on that
-        syncMenuShortcuts()
-        terminalManager.relabelAllTabs()
-
-        // Config could change window appearance. We wrap this in an async queue because when
-        // this is called as part of application launch it can deadlock with an internal
-        // AppKit mutex on the appearance.
-        DispatchQueue.main.async { self.syncAppearance() }
-
-        // Update all of our windows
-        terminalManager.windows.forEach { window in
-            window.controller.configDidReload()
-        }
-
-        // If we have configuration errors, we need to show them.
-        let c = ConfigurationErrorsController.sharedInstance
-        c.errors = state.config.errors
-        if (c.errors.count > 0) {
-            if (c.window == nil || !c.window!.isVisible) {
-                c.showWindow(self)
-            }
-        }
-
-        // We need to handle our global event tap depending on if there are global
-        // events that we care about in Ghostty.
-        if (ghostty_app_has_global_keybinds(ghostty.app!)) {
-            if (timeSinceLaunch > 5) {
-                // If the process has been running for awhile we enable right away
-                // because no windows are likely to pop up.
-                GlobalEventTap.shared.enable()
-            } else {
-                // If the process just started, we wait a couple seconds to allow
-                // the initial windows and so on to load so our permissions dialog
-                // doesn't get buried.
-                DispatchQueue.main.asyncAfter(deadline: .now() + .seconds(2)) {
-                    GlobalEventTap.shared.enable()
-                }
-            }
-        } else {
-            GlobalEventTap.shared.disable()
-        }
-    }
-
-    /// Sync the appearance of our app with the theme specified in the config.
-    private func syncAppearance() {
-        guard let theme = ghostty.config.windowTheme else { return }
-        switch (theme) {
-        case "dark":
-            let appearance = NSAppearance(named: .darkAqua)
-            NSApplication.shared.appearance = appearance
-
-        case "light":
-            let appearance = NSAppearance(named: .aqua)
-            NSApplication.shared.appearance = appearance
-
-        case "auto":
-            let color = OSColor(ghostty.config.backgroundColor)
-            let appearance = NSAppearance(named: color.isLightColor ? .aqua : .darkAqua)
-            NSApplication.shared.appearance = appearance
-
-        default:
-            NSApplication.shared.appearance = nil
-        }
-    }
-
     //MARK: - Dock Menu
 
     private func reloadDockMenu() {
@@ -629,7 +648,7 @@ class AppDelegate: NSObject,
         if quickController == nil {
             quickController = QuickTerminalController(
                 ghostty,
-                position: ghostty.config.quickTerminalPosition
+                position: derivedConfig.quickTerminalPosition
             )
         }
 
@@ -655,4 +674,22 @@ class AppDelegate: NSObject,
 
         isVisible.toggle()
     }
+
+    private struct DerivedConfig {
+        let initialWindow: Bool
+        let shouldQuitAfterLastWindowClosed: Bool
+        let quickTerminalPosition: QuickTerminalPosition
+
+        init() {
+            self.initialWindow = true
+            self.shouldQuitAfterLastWindowClosed = false
+            self.quickTerminalPosition = .top
+        }
+
+        init(_ config: Ghostty.Config) {
+            self.initialWindow = config.initialWindow
+            self.shouldQuitAfterLastWindowClosed = config.shouldQuitAfterLastWindowClosed
+            self.quickTerminalPosition = config.quickTerminalPosition
+        }
+    }
 }

macos/Sources/Features/QuickTerminal/QuickTerminalController.swift

@@ -18,12 +18,16 @@ class QuickTerminalController: BaseTerminalController {
     /// application to the front.
     private var previousApp: NSRunningApplication? = nil
 
+    /// The configuration derived from the Ghostty config so we don't need to rely on references.
+    private var derivedConfig: DerivedConfig
+
     init(_ ghostty: Ghostty.App,
          position: QuickTerminalPosition = .top,
          baseConfig base: Ghostty.SurfaceConfiguration? = nil,
          surfaceTree tree: Ghostty.SplitNode? = nil
     ) {
         self.position = position
+        self.derivedConfig = DerivedConfig(ghostty.config)
         super.init(ghostty, baseConfig: base, surfaceTree: tree)
 
         // Setup our notifications for behaviors
@@ -35,8 +39,8 @@ class QuickTerminalController: BaseTerminalController {
             object: nil)
         center.addObserver(
             self,
-            selector: #selector(ghosttyDidReloadConfig),
+            selector: #selector(ghosttyConfigDidChange(_:)),
-            name: Ghostty.Notification.ghosttyDidReloadConfig,
+            name: .ghosttyConfigDidChange,
             object: nil)
     }
 
@@ -64,7 +68,7 @@ class QuickTerminalController: BaseTerminalController {
         window.isRestorable = false
 
         // Setup our configured appearance that we support.
-        syncAppearance()
+        syncAppearance(ghostty.config)
 
         // Setup our initial size based on our configured position
         position.setLoaded(window)
@@ -186,7 +190,7 @@ class QuickTerminalController: BaseTerminalController {
     }
 
     private func animateWindowIn(window: NSWindow, from position: QuickTerminalPosition) {
-        guard let screen = ghostty.config.quickTerminalScreen.screen else { return }
+        guard let screen = derivedConfig.quickTerminalScreen.screen else { return }
 
         // Move our window off screen to the top
         position.setInitial(in: window, on: screen)
@@ -197,7 +201,7 @@ class QuickTerminalController: BaseTerminalController {
         // Run the animation that moves our window into the proper place and makes
         // it visible.
         NSAnimationContext.runAnimationGroup({ context in
-            context.duration = ghostty.config.quickTerminalAnimationDuration
+            context.duration = derivedConfig.quickTerminalAnimationDuration
             context.timingFunction = .init(name: .easeIn)
             position.setFinal(in: window.animator(), on: screen)
         }, completionHandler: {
@@ -287,7 +291,7 @@ class QuickTerminalController: BaseTerminalController {
         }
 
         NSAnimationContext.runAnimationGroup({ context in
-            context.duration = ghostty.config.quickTerminalAnimationDuration
+            context.duration = derivedConfig.quickTerminalAnimationDuration
             context.timingFunction = .init(name: .easeIn)
             position.setInitial(in: window.animator(), on: screen)
         }, completionHandler: {
@@ -297,7 +301,7 @@ class QuickTerminalController: BaseTerminalController {
         })
     }
 
-    private func syncAppearance() {
+    private func syncAppearance(_ config: Ghostty.Config) {
         guard let window else { return }
 
         // If our window is not visible, then delay this. This is possible specifically
@@ -306,7 +310,7 @@ class QuickTerminalController: BaseTerminalController {
         // APIs such as window blur have no effect unless the window is visible.
         guard window.isVisible else {
             // Weak window so that if the window changes or is destroyed we aren't holding a ref
-            DispatchQueue.main.async { [weak self] in self?.syncAppearance() }
+            DispatchQueue.main.async { [weak self] in self?.syncAppearance(config) }
             return
         }
 
@@ -314,7 +318,7 @@ class QuickTerminalController: BaseTerminalController {
         // to "native" which is typically P3. There is a lot more resources
         // covered in this GitHub issue: https://github.com/mitchellh/ghostty/pull/376
         // Ghostty defaults to sRGB but this can be overridden.
-        switch (ghostty.config.windowColorspace) {
+        switch (config.windowColorspace) {
         case "display-p3":
             window.colorSpace = .displayP3
         case "srgb":
@@ -324,7 +328,7 @@ class QuickTerminalController: BaseTerminalController {
         }
 
         // If we have window transparency then set it transparent. Otherwise set it opaque.
-        if (ghostty.config.backgroundOpacity < 1) {
+        if (config.backgroundOpacity < 1) {
             window.isOpaque = false
 
             // This is weird, but we don't use ".clear" because this creates a look that
@@ -371,8 +375,35 @@ class QuickTerminalController: BaseTerminalController {
         toggleFullscreen(mode: .nonNative)
     }
 
-    @objc private func ghosttyDidReloadConfig(notification: SwiftUI.Notification) {
+    @objc private func ghosttyConfigDidChange(_ notification: Notification) {
-        syncAppearance()
+        // We only care if the configuration is a global configuration, not a
+        // surface-specific one.
+        guard notification.object == nil else { return }
+
+        // Get our managed configuration object out
+        guard let config = notification.userInfo?[
+            Notification.Name.GhosttyConfigChangeKey
+        ] as? Ghostty.Config else { return }
+
+        // Update our derived config
+        self.derivedConfig = DerivedConfig(config)
+
+        syncAppearance(config)
+    }
+
+    private struct DerivedConfig {
+        let quickTerminalScreen: QuickTerminalScreen
+        let quickTerminalAnimationDuration: Double
+
+        init() {
+            self.quickTerminalScreen = .main
+            self.quickTerminalAnimationDuration = 0.2
+        }
+
+        init(_ config: Ghostty.Config) {
+            self.quickTerminalScreen = config.quickTerminalScreen
+            self.quickTerminalAnimationDuration = config.quickTerminalAnimationDuration
+        }
     }
 }
 

macos/Sources/Features/Terminal/BaseTerminalController.swift

@@ -60,6 +60,9 @@ class BaseTerminalController: NSWindowController,
     /// The previous frame information from the window
     private var savedFrame: SavedFrame? = nil
 
+    /// The configuration derived from the Ghostty config so we don't need to rely on references.
+    private var derivedConfig: DerivedConfig
+
     struct SavedFrame {
         let window: NSRect
         let screen: NSRect
@@ -74,6 +77,7 @@ class BaseTerminalController: NSWindowController,
          surfaceTree tree: Ghostty.SplitNode? = nil
     ) {
         self.ghostty = ghostty
+        self.derivedConfig = DerivedConfig(ghostty.config)
 
         super.init(window: nil)
 
@@ -93,6 +97,11 @@ class BaseTerminalController: NSWindowController,
             selector: #selector(didChangeScreenParametersNotification),
             name: NSApplication.didChangeScreenParametersNotification,
             object: nil)
+        center.addObserver(
+            self,
+            selector: #selector(ghosttyConfigDidChangeBase(_:)),
+            name: .ghosttyConfigDidChange,
+            object: nil)
 
         // Listen for local events that we need to know of outside of
         // single surface handlers.
@@ -191,6 +200,20 @@ class BaseTerminalController: NSWindowController,
         window.setFrame(newFrame, display: true)
     }
 
+    @objc private func ghosttyConfigDidChangeBase(_ notification: Notification) {
+        // We only care if the configuration is a global configuration, not a
+        // surface-specific one.
+        guard notification.object == nil else { return }
+        
+        // Get our managed configuration object out
+        guard let config = notification.userInfo?[
+            Notification.Name.GhosttyConfigChangeKey
+        ] as? Ghostty.Config else { return }
+        
+        // Update our derived config
+        self.derivedConfig = DerivedConfig(config)
+    }
+
     // MARK: Local Events
 
     private func localEventHandler(_ event: NSEvent) -> NSEvent? {
@@ -245,7 +268,7 @@ class BaseTerminalController: NSWindowController,
     func pwdDidChange(to: URL?) {
         guard let window else { return }
 
-        if ghostty.config.macosTitlebarProxyIcon == .visible {
+        if derivedConfig.macosTitlebarProxyIcon == .visible {
             // Use the 'to' URL directly
             window.representedURL = to
         } else {
@@ -255,7 +278,7 @@ class BaseTerminalController: NSWindowController,
 
 
     func cellSizeDidChange(to: NSSize) {
-        guard ghostty.config.windowStepResize else { return }
+        guard derivedConfig.windowStepResize else { return }
         self.window?.contentResizeIncrements = to
     }
 
@@ -563,4 +586,19 @@ class BaseTerminalController: NSWindowController,
         guard let surface = focusedSurface?.surface else { return }
         ghostty.resetTerminal(surface: surface)
     }
+
+    private struct DerivedConfig {
+        let macosTitlebarProxyIcon: Ghostty.MacOSTitlebarProxyIcon
+        let windowStepResize: Bool
+
+        init() {
+            self.macosTitlebarProxyIcon = .visible
+            self.windowStepResize = false
+        }
+
+        init(_ config: Ghostty.Config) {
+            self.macosTitlebarProxyIcon = config.macosTitlebarProxyIcon
+            self.windowStepResize = config.windowStepResize
+        }
+    }
 }

macos/Sources/Features/Terminal/TerminalController.swift

@@ -1,6 +1,7 @@
 import Foundation
 import Cocoa
 import SwiftUI
+import Combine
 import GhosttyKit
 
 /// A classic, tabbed terminal experience.
@@ -20,6 +21,12 @@ class TerminalController: BaseTerminalController {
     /// For example, terminals executing custom scripts are not restorable.
     private var restorable: Bool = true
 
+    /// The configuration derived from the Ghostty config so we don't need to rely on references.
+    private var derivedConfig: DerivedConfig
+
+    /// The notification cancellable for focused surface property changes.
+    private var surfaceAppearanceCancellables: Set<AnyCancellable> = []
+
     init(_ ghostty: Ghostty.App,
          withBaseConfig base: Ghostty.SurfaceConfiguration? = nil,
          withSurfaceTree tree: Ghostty.SplitNode? = nil
@@ -31,6 +38,9 @@ class TerminalController: BaseTerminalController {
         // restoration.
         self.restorable = (base?.command ?? "") == ""
 
+        // Setup our initial derived config based on the current app config
+        self.derivedConfig = DerivedConfig(ghostty.config)
+
         super.init(ghostty, baseConfig: base, surfaceTree: tree)
 
         // Setup our notifications for behaviors
@@ -50,6 +60,12 @@ class TerminalController: BaseTerminalController {
             selector: #selector(onGotoTab),
             name: Ghostty.Notification.ghosttyGotoTab,
             object: nil)
+        center.addObserver(
+            self,
+            selector: #selector(ghosttyConfigDidChange(_:)),
+            name: .ghosttyConfigDidChange,
+            object: nil
+        )
         center.addObserver(
             self,
             selector: #selector(onFrameDidChange),
@@ -80,10 +96,38 @@ class TerminalController: BaseTerminalController {
 
     //MARK: - Methods
 
-    func configDidReload() {
+    @objc private func ghosttyConfigDidChange(_ notification: Notification) {
-        guard let window = window as? TerminalWindow else { return }
+        // Get our managed configuration object out
-        window.focusFollowsMouse = ghostty.config.focusFollowsMouse
+        guard let config = notification.userInfo?[
-        syncAppearance()
+            Notification.Name.GhosttyConfigChangeKey
+        ] as? Ghostty.Config else { return }
+
+        // If this is an app-level config update then we update some things.
+        if (notification.object == nil) {
+            // Update our derived config
+            self.derivedConfig = DerivedConfig(config)
+
+            guard let window = window as? TerminalWindow else { return }
+            window.focusFollowsMouse = config.focusFollowsMouse
+
+            // If we have no surfaces in our window (is that possible?) then we update
+            // our window appearance based on the root config. If we have surfaces, we
+            // don't call this because the TODO
+            if surfaceTree == nil {
+                syncAppearance(.init(config))
+            }
+
+            return
+        }
+
+        // This is a surface-level config update. If we have the surface, we
+        // update our appearance based on it.
+        guard let surfaceView = notification.object as? Ghostty.SurfaceView else { return }
+        guard surfaceTree?.contains(view: surfaceView) ?? false else { return }
+
+        // We can't use surfaceView.derivedConfig because it may not be updated
+        // yet since it also responds to notifications.
+        syncAppearance(.init(config))
     }
 
     /// Update the accessory view of each tab according to the keyboard
@@ -144,28 +188,23 @@ class TerminalController: BaseTerminalController {
         self.relabelTabs()
     }
 
-    private func syncAppearance() {
+    private func syncAppearance(_ surfaceConfig: Ghostty.SurfaceView.DerivedConfig) {
         guard let window = self.window as? TerminalWindow else { return }
 
-        // If our window is not visible, then delay this. This is possible specifically
+        // If our window is not visible, then we do nothing. Some things such as blurring
-        // during state restoration but probably in other scenarios as well. To delay,
+        // have no effect if the window is not visible. Ultimately, we'll have this called
-        // we just loop directly on the dispatch queue. We have to delay because some
+        // at some point when a surface becomes focused.
-        // APIs such as window blur have no effect unless the window is visible.
+        guard window.isVisible else { return }
-        guard window.isVisible else {
-            // Weak window so that if the window changes or is destroyed we aren't holding a ref
-            DispatchQueue.main.async { [weak self] in self?.syncAppearance() }
-            return
-        }
 
         // Set the font for the window and tab titles.
-        if let titleFontName = ghostty.config.windowTitleFontFamily {
+        if let titleFontName = surfaceConfig.windowTitleFontFamily {
             window.titlebarFont = NSFont(name: titleFontName, size: NSFont.systemFontSize)
         } else {
             window.titlebarFont = nil
         }
 
         // If we have window transparency then set it transparent. Otherwise set it opaque.
-        if (ghostty.config.backgroundOpacity < 1) {
+        if (surfaceConfig.backgroundOpacity < 1) {
             window.isOpaque = false
 
             // This is weird, but we don't use ".clear" because this creates a look that
@@ -179,14 +218,26 @@ class TerminalController: BaseTerminalController {
             window.backgroundColor = .windowBackgroundColor
         }
 
-        window.hasShadow = ghostty.config.macosWindowShadow
+        window.hasShadow = surfaceConfig.macosWindowShadow
 
         guard window.hasStyledTabs else { return }
 
-        // The titlebar is always updated. We don't need to worry about opacity
+        // Our background color depends on if our focused surface borders the top or not.
-        // because we handle it here.
+        // If it does, we match the focused surface. If it doesn't, we use the app
-        let backgroundColor = OSColor(ghostty.config.backgroundColor)
+        // configuration.
-        window.titlebarColor = backgroundColor.withAlphaComponent(ghostty.config.backgroundOpacity)
+        let backgroundColor: OSColor
+        if let surfaceTree {
+            if let focusedSurface, surfaceTree.doesBorderTop(view: focusedSurface) {
+                backgroundColor = OSColor(focusedSurface.backgroundColor ?? surfaceConfig.backgroundColor)
+            } else {
+                // We don't have a focused surface or our surface doesn't border the
+                // top. We choose to match the color of the top-left most surface.
+                backgroundColor = OSColor(surfaceTree.topLeft().backgroundColor ?? derivedConfig.backgroundColor)
+            }
+        } else {
+            backgroundColor = OSColor(self.derivedConfig.backgroundColor)
+        }
+        window.titlebarColor = backgroundColor.withAlphaComponent(surfaceConfig.backgroundOpacity)
 
         if (window.isOpaque) {
             // Bg color is only synced if we have no transparency. This is because
@@ -210,6 +261,12 @@ class TerminalController: BaseTerminalController {
     override func windowDidLoad() {
         guard let window = window as? TerminalWindow else { return }
 
+        // I copy this because we may change the source in the future but also because
+        // I regularly audit our codebase for "ghostty.config" access because generally
+        // you shouldn't use it. Its safe in this case because for a new window we should
+        // use whatever the latest app-level config is.
+        let config = ghostty.config
+
         // Setting all three of these is required for restoration to work.
         window.isRestorable = restorable
         if (restorable) {
@@ -218,13 +275,13 @@ class TerminalController: BaseTerminalController {
         }
 
         // If window decorations are disabled, remove our title
-        if (!ghostty.config.windowDecorations) { window.styleMask.remove(.titled) }
+        if (!config.windowDecorations) { window.styleMask.remove(.titled) }
 
         // Terminals typically operate in sRGB color space and macOS defaults
         // to "native" which is typically P3. There is a lot more resources
         // covered in this GitHub issue: https://github.com/mitchellh/ghostty/pull/376
         // Ghostty defaults to sRGB but this can be overridden.
-        switch (ghostty.config.windowColorspace) {
+        switch (config.windowColorspace) {
         case "display-p3":
             window.colorSpace = .displayP3
         case "srgb":
@@ -256,30 +313,30 @@ class TerminalController: BaseTerminalController {
         window.center()
 
         // Make sure our theme is set on the window so styling is correct.
-        if let windowTheme = ghostty.config.windowTheme {
+        if let windowTheme = config.windowTheme {
             window.windowTheme = .init(rawValue: windowTheme)
         }
 
         // Handle titlebar tabs config option. Something about what we do while setting up the
         // titlebar tabs interferes with the window restore process unless window.tabbingMode
         // is set to .preferred, so we set it, and switch back to automatic as soon as we can.
-        if (ghostty.config.macosTitlebarStyle == "tabs") {
+        if (config.macosTitlebarStyle == "tabs") {
             window.tabbingMode = .preferred
             window.titlebarTabs = true
             DispatchQueue.main.async {
                 window.tabbingMode = .automatic
             }
-        } else if (ghostty.config.macosTitlebarStyle == "transparent") {
+        } else if (config.macosTitlebarStyle == "transparent") {
             window.transparentTabs = true
         }
 
         if window.hasStyledTabs {
             // Set the background color of the window
-            let backgroundColor = NSColor(ghostty.config.backgroundColor)
+            let backgroundColor = NSColor(config.backgroundColor)
             window.backgroundColor = backgroundColor
 
             // This makes sure our titlebar renders correctly when there is a transparent background
-            window.titlebarColor = backgroundColor.withAlphaComponent(ghostty.config.backgroundOpacity)
+            window.titlebarColor = backgroundColor.withAlphaComponent(config.backgroundOpacity)
         }
 
         // Initialize our content view to the SwiftUI root
@@ -290,7 +347,7 @@ class TerminalController: BaseTerminalController {
         ))
 
         // If our titlebar style is "hidden" we adjust the style appropriately
-        if (ghostty.config.macosTitlebarStyle == "hidden") {
+        if (config.macosTitlebarStyle == "hidden") {
             window.styleMask = [
                 // We need `titled` in the mask to get the normal window frame
                 .titled,
@@ -345,10 +402,12 @@ class TerminalController: BaseTerminalController {
             }
         }
 
-        window.focusFollowsMouse = ghostty.config.focusFollowsMouse
+        window.focusFollowsMouse = config.focusFollowsMouse
 
-        // Apply any additional appearance-related properties to the new window.
+        // Apply any additional appearance-related properties to the new window. We
-        syncAppearance()
+        // apply this based on the root config but change it later based on surface
+        // config (see focused surface change callback).
+        syncAppearance(.init(config))
     }
 
     // Shows the "+" button in the tab bar, responds to that click.
@@ -464,7 +523,7 @@ class TerminalController: BaseTerminalController {
 
         // Custom toolbar-based title used when titlebar tabs are enabled.
         if let toolbar = window.toolbar as? TerminalToolbar {
-            if (window.titlebarTabs || ghostty.config.macosTitlebarStyle == "hidden") {
+            if (window.titlebarTabs || derivedConfig.macosTitlebarStyle == "hidden") {
                 // Updating the title text as above automatically reveals the
                 // native title view in macOS 15.0 and above. Since we're using
                 // a custom view instead, we need to re-hide it.
@@ -485,6 +544,36 @@ class TerminalController: BaseTerminalController {
         window.surfaceIsZoomed = to
     }
 
+    override func focusedSurfaceDidChange(to: Ghostty.SurfaceView?) {
+        super.focusedSurfaceDidChange(to: to)
+
+        // We always cancel our event listener
+        surfaceAppearanceCancellables.removeAll()
+
+        // When our focus changes, we update our window appearance based on the
+        // currently focused surface.
+        guard let focusedSurface else { return }
+        syncAppearance(focusedSurface.derivedConfig)
+
+        // We also want to get notified of certain changes to update our appearance.
+        focusedSurface.$derivedConfig
+            .sink { [weak self, weak focusedSurface] _ in self?.syncAppearanceOnPropertyChange(focusedSurface) }
+            .store(in: &surfaceAppearanceCancellables)
+        focusedSurface.$backgroundColor
+            .sink { [weak self, weak focusedSurface] _ in self?.syncAppearanceOnPropertyChange(focusedSurface) }
+            .store(in: &surfaceAppearanceCancellables)
+    }
+
+    private func syncAppearanceOnPropertyChange(_ surface: Ghostty.SurfaceView?) {
+        guard let surface else { return }
+        DispatchQueue.main.async { [weak self, weak surface] in
+            guard let surface else { return }
+            guard let self else { return }
+            guard self.focusedSurface == surface else { return }
+            self.syncAppearance(surface.derivedConfig)
+        }
+    }
+
     //MARK: - Notifications
 
     @objc private func onMoveTab(notification: SwiftUI.Notification) {
@@ -593,4 +682,19 @@ class TerminalController: BaseTerminalController {
 
         toggleFullscreen(mode: fullscreenMode)
     }
+
+    private struct DerivedConfig {
+        let backgroundColor: Color
+        let macosTitlebarStyle: String
+
+        init() {
+            self.backgroundColor = Color(NSColor.windowBackgroundColor)
+            self.macosTitlebarStyle = "system"
+        }
+
+        init(_ config: Ghostty.Config) {
+            self.backgroundColor = config.backgroundColor
+            self.macosTitlebarStyle = config.macosTitlebarStyle
+        }
+    }
 }

macos/Sources/Features/Terminal/TerminalManager.swift

@@ -37,8 +37,12 @@ class TerminalManager {
         return windows.last
     }
 
+    /// The configuration derived from the Ghostty config so we don't need to rely on references.
+    private var derivedConfig: DerivedConfig
+
     init(_ ghostty: Ghostty.App) {
         self.ghostty = ghostty
+        self.derivedConfig = DerivedConfig(ghostty.config)
 
         let center = NotificationCenter.default
         center.addObserver(
@@ -51,6 +55,11 @@ class TerminalManager {
             selector: #selector(onNewWindow),
             name: Ghostty.Notification.ghosttyNewWindow,
             object: nil)
+        center.addObserver(
+            self,
+            selector: #selector(ghosttyConfigDidChange(_:)),
+            name: .ghosttyConfigDidChange,
+            object: nil)
     }
 
     deinit {
@@ -70,8 +79,8 @@ class TerminalManager {
         if let parent = focusedSurface?.window,
             parent.styleMask.contains(.fullScreen) {
             window.toggleFullScreen(nil)
-        } else if ghostty.config.windowFullscreen {
+        } else if derivedConfig.windowFullscreen {
-            switch (ghostty.config.windowFullscreenMode) {
+            switch (derivedConfig.windowFullscreenMode) {
             case .native:
                 // Native has to be done immediately so that our stylemask contains
                 // fullscreen for the logic later in this method.
@@ -81,7 +90,7 @@ class TerminalManager {
                 // If we're non-native then we have to do it on a later loop
                 // so that the content view is setup.
                 DispatchQueue.main.async {
-                    c.toggleFullscreen(mode: self.ghostty.config.windowFullscreenMode)
+                    c.toggleFullscreen(mode: self.derivedConfig.windowFullscreenMode)
                 }
             }
         }
@@ -159,9 +168,9 @@ class TerminalManager {
 
         // If we have the "hidden" titlebar style we want to create new
         // tabs as windows instead, so just skip adding it to the parent.
-        if (ghostty.config.macosTitlebarStyle != "hidden") {
+        if (derivedConfig.macosTitlebarStyle != "hidden") {
             // Add the window to the tab group and show it.
-            switch ghostty.config.windowNewTabPosition {
+            switch derivedConfig.windowNewTabPosition {
             case "end":
                 // If we already have a tab group and we want the new tab to open at the end,
                 // then we use the last window in the tab group as the parent.
@@ -325,4 +334,39 @@ class TerminalManager {
 
         self.newTab(to: window, withBaseConfig: config)
     }
+
+    @objc private func ghosttyConfigDidChange(_ notification: Notification) {
+        // We only care if the configuration is a global configuration, not a
+        // surface-specific one.
+        guard notification.object == nil else { return }
+
+        // Get our managed configuration object out
+        guard let config = notification.userInfo?[
+            Notification.Name.GhosttyConfigChangeKey
+        ] as? Ghostty.Config else { return }
+
+        // Update our derived config
+        self.derivedConfig = DerivedConfig(config)
+    }
+
+    private struct DerivedConfig {
+        let windowFullscreen: Bool
+        let windowFullscreenMode: FullscreenMode
+        let macosTitlebarStyle: String
+        let windowNewTabPosition: String
+
+        init() {
+            self.windowFullscreen = false
+            self.windowFullscreenMode = .native
+            self.macosTitlebarStyle = "transparent"
+            self.windowNewTabPosition = ""
+        }
+
+        init(_ config: Ghostty.Config) {
+            self.windowFullscreen = config.windowFullscreen
+            self.windowFullscreenMode = config.windowFullscreenMode
+            self.macosTitlebarStyle = config.macosTitlebarStyle
+            self.windowNewTabPosition = config.windowNewTabPosition
+        }
+    }
 }

macos/Sources/Features/Terminal/TerminalRestorable.swift

@@ -65,8 +65,10 @@ class TerminalWindowRestoration: NSObject, NSWindowRestoration {
         }
 
         // If our configuration is "never" then we never restore the state
-        // no matter what.
+        // no matter what. Note its safe to use "ghostty.config" directly here
-        if (appDelegate.terminalManager.ghostty.config.windowSaveState == "never") {
+        // because window restoration is only ever invoked on app start so we
+        // don't have to deal with config reloads.
+        if (appDelegate.ghostty.config.windowSaveState == "never") {
             completionHandler(nil, nil)
             return
         }

macos/Sources/Ghostty/Ghostty.Action.swift

@@ -1,3 +1,4 @@
+import SwiftUI
 import GhosttyKit
 
 extension Ghostty {
@@ -5,6 +6,33 @@ extension Ghostty {
 }
 
 extension Ghostty.Action {
+    struct ColorChange {
+        let kind: Kind
+        let color: Color
+
+        enum Kind {
+            case foreground
+            case background
+            case cursor
+            case palette(index: UInt8)
+        }
+
+        init(c: ghostty_action_color_change_s) {
+            switch (c.kind) {
+            case GHOSTTY_ACTION_COLOR_KIND_FOREGROUND:
+                self.kind = .foreground
+            case GHOSTTY_ACTION_COLOR_KIND_BACKGROUND:
+                self.kind = .background
+            case GHOSTTY_ACTION_COLOR_KIND_CURSOR:
+                self.kind = .cursor
+            default:
+                self.kind = .palette(index: UInt8(c.kind.rawValue))
+            }
+
+            self.color = Color(red: Double(c.r) / 255, green: Double(c.g) / 255, blue: Double(c.b) / 255)
+        }
+    }
+
     struct MoveTab {
         let amount: Int
 

macos/Sources/Ghostty/Ghostty.App.swift

@@ -3,9 +3,6 @@ import UserNotifications
 import GhosttyKit
 
 protocol GhosttyAppDelegate: AnyObject {
-    /// Called when the configuration did finish reloading.
-    func configDidReload(_ app: Ghostty.App)
-
     #if os(macOS)
     /// Called when a callback needs access to a specific surface. This should return nil
     /// when the surface is no longer valid.
@@ -380,16 +377,6 @@ extension Ghostty {
             let state = Unmanaged<Self>.fromOpaque(userdata!).takeUnretainedValue()
             state.config = newConfig
 
-            // If we have a delegate, notify.
-            if let delegate = state.delegate {
-                delegate.configDidReload(state)
-            }
-
-            // Send an event out
-            NotificationCenter.default.post(
-                name: Ghostty.Notification.ghosttyDidReloadConfig,
-                object: nil)
-
             return newConfig.config
         }
 
@@ -524,8 +511,12 @@ extension Ghostty {
             case GHOSTTY_ACTION_KEY_SEQUENCE:
                 keySequence(app, target: target, v: action.action.key_sequence)
 
+            case GHOSTTY_ACTION_CONFIG_CHANGE:
+                configChange(app, target: target, v: action.action.config_change)
+
             case GHOSTTY_ACTION_COLOR_CHANGE:
-                fallthrough
+                colorChange(app, target: target, change: action.action.color_change)
+
             case GHOSTTY_ACTION_CLOSE_ALL_WINDOWS:
                 fallthrough
             case GHOSTTY_ACTION_TOGGLE_TAB_OVERVIEW:
@@ -1159,6 +1150,71 @@ extension Ghostty {
             }
         }
 
+        private static func configChange(
+            _ app: ghostty_app_t,
+            target: ghostty_target_s,
+            v: ghostty_action_config_change_s) {
+                logger.info("config change notification")
+
+                // Clone the config so we own the memory. It'd be nicer to not have to do
+                // this but since we async send the config out below we have to own the lifetime.
+                // A future improvement might be to add reference counting to config or
+                // something so apprt's do not have to do this.
+                let config = Config(clone: v.config)
+
+                switch (target.tag) {
+                case GHOSTTY_TARGET_APP:
+                    NotificationCenter.default.post(
+                        name: .ghosttyConfigDidChange,
+                        object: nil,
+                        userInfo: [
+                            SwiftUI.Notification.Name.GhosttyConfigChangeKey: config,
+                        ]
+                    )
+                    return
+
+                case GHOSTTY_TARGET_SURFACE:
+                    guard let surface = target.target.surface else { return }
+                    guard let surfaceView = self.surfaceView(from: surface) else { return }
+                    NotificationCenter.default.post(
+                        name: .ghosttyConfigDidChange,
+                        object: surfaceView,
+                        userInfo: [
+                            SwiftUI.Notification.Name.GhosttyConfigChangeKey: config,
+                        ]
+                    )
+
+                default:
+                    assertionFailure()
+                }
+            }
+
+        private static func colorChange(
+            _ app: ghostty_app_t,
+            target: ghostty_target_s,
+            change: ghostty_action_color_change_s) {
+                switch (target.tag) {
+                case GHOSTTY_TARGET_APP:
+                    Ghostty.logger.warning("color change does nothing with an app target")
+                    return
+
+                case GHOSTTY_TARGET_SURFACE:
+                    guard let surface = target.target.surface else { return }
+                    guard let surfaceView = self.surfaceView(from: surface) else { return }
+                    NotificationCenter.default.post(
+                        name: .ghosttyColorDidChange,
+                        object: surfaceView,
+                        userInfo: [
+                            SwiftUI.Notification.Name.GhosttyColorChangeKey: Action.ColorChange(c: change)
+                        ]
+                    )
+
+                default:
+                    assertionFailure()
+                }
+        }
+
+
         // MARK: User Notifications
 
         /// Handle a received user notification. This is called when a user notification is clicked or dismissed by the user

macos/Sources/Ghostty/Ghostty.Config.swift

@@ -39,6 +39,10 @@ extension Ghostty {
             }
         }
 
+        init(clone config: ghostty_config_t) {
+            self.config = ghostty_config_clone(config)
+        }
+
         deinit {
             self.config = nil
         }

macos/Sources/Ghostty/Ghostty.SplitNode.swift

@@ -38,6 +38,16 @@ extension Ghostty {
             }
         }
 
+        func topLeft() -> SurfaceView {
+            switch (self) {
+            case .leaf(let leaf):
+                return leaf.surface
+
+            case .split(let container):
+                return container.topLeft.topLeft()
+            }
+        }
+
         /// Returns the view that would prefer receiving focus in this tree. This is always the
         /// top-left-most view. This is used when creating a split or closing a split to find the
         /// next view to send focus to.
@@ -136,6 +146,24 @@ extension Ghostty {
             }
         }
 
+        /// Returns true if the surface borders the top. Assumes the view is in the tree.
+        func doesBorderTop(view: SurfaceView) -> Bool {
+            switch (self) {
+            case .leaf(let leaf):
+                return leaf.surface == view
+
+            case .split(let container):
+                switch (container.direction) {
+                case .vertical:
+                    return container.topLeft.doesBorderTop(view: view)
+
+                case .horizontal:
+                    return container.topLeft.doesBorderTop(view: view) ||
+                        container.bottomRight.doesBorderTop(view: view)
+                }
+            }
+        }
+
         // MARK: - Sequence
 
         func makeIterator() -> IndexingIterator<[Leaf]> {

macos/Sources/Ghostty/Package.swift

@@ -206,6 +206,14 @@ extension Ghostty {
 // MARK: Surface Notification
 
 extension Notification.Name {
+    /// Configuration change. If the object is nil then it is app-wide. Otherwise its surface-specific.
+    static let ghosttyConfigDidChange = Notification.Name("com.mitchellh.ghostty.configDidChange")
+    static let GhosttyConfigChangeKey = ghosttyConfigDidChange.rawValue
+
+    /// Color change. Object is the surface changing.
+    static let ghosttyColorDidChange = Notification.Name("com.mitchellh.ghostty.ghosttyColorDidChange")
+    static let GhosttyColorChangeKey = ghosttyColorDidChange.rawValue
+
     /// Goto tab. Has tab index in the userinfo.
     static let ghosttyMoveTab = Notification.Name("com.mitchellh.ghostty.moveTab")
     static let GhosttyMoveTabKey = ghosttyMoveTab.rawValue
@@ -217,9 +225,6 @@ extension Ghostty.Notification {
     /// Used to pass a configuration along when creating a new tab/window/split.
     static let NewSurfaceConfigKey = "com.mitchellh.ghostty.newSurfaceConfig"
 
-    /// Posted when the application configuration is reloaded.
-    static let ghosttyDidReloadConfig = Notification.Name("com.mitchellh.ghostty.didReloadConfig")
-
     /// Posted when a new split is requested. The sending object will be the surface that had focus. The
     /// userdata has one key "direction" with the direction to split to.
     static let ghosttyNewSplit = Notification.Name("com.mitchellh.ghostty.newSplit")

macos/Sources/Ghostty/SurfaceView_AppKit.swift

@@ -48,6 +48,13 @@ extension Ghostty {
         // Whether the pointer should be visible or not
         @Published private(set) var pointerStyle: BackportPointerStyle = .default
 
+        /// The configuration derived from the Ghostty config so we don't need to rely on references.
+        @Published private(set) var derivedConfig: DerivedConfig
+
+        /// The background color within the color palette of the surface. This is only set if it is
+        /// dynamically updated. Otherwise, the background color is the default background color.
+        @Published private(set) var backgroundColor: Color? = nil
+
         // An initial size to request for a window. This will only affect
         // then the view is moved to a new window.
         var initialSize: NSSize? = nil
@@ -114,6 +121,13 @@ extension Ghostty {
             self.markedText = NSMutableAttributedString()
             self.uuid = uuid ?? .init()
 
+            // Our initial config always is our application wide config.
+            if let appDelegate = NSApplication.shared.delegate as? AppDelegate {
+                self.derivedConfig = DerivedConfig(appDelegate.ghostty.config)
+            } else {
+                self.derivedConfig = DerivedConfig()
+            }
+
             // Initialize with some default frame size. The important thing is that this
             // is non-zero so that our layer bounds are non-zero so that our renderer
             // can do SOMETHING.
@@ -137,6 +151,16 @@ extension Ghostty {
                 selector: #selector(ghosttyDidEndKeySequence),
                 name: Ghostty.Notification.didEndKeySequence,
                 object: self)
+            center.addObserver(
+                self,
+                selector: #selector(ghosttyConfigDidChange(_:)),
+                name: .ghosttyConfigDidChange,
+                object: self)
+            center.addObserver(
+                self,
+                selector: #selector(ghosttyColorDidChange(_:)),
+                name: .ghosttyColorDidChange,
+                object: self)
             center.addObserver(
                 self,
                 selector: #selector(windowDidChangeScreen),
@@ -333,6 +357,31 @@ extension Ghostty {
             keySequence = []
         }
 
+        @objc private func ghosttyConfigDidChange(_ notification: SwiftUI.Notification) {
+            // Get our managed configuration object out
+            guard let config = notification.userInfo?[
+                SwiftUI.Notification.Name.GhosttyConfigChangeKey
+            ] as? Ghostty.Config else { return }
+
+            // Update our derived config
+            self.derivedConfig = DerivedConfig(config)
+        }
+
+        @objc private func ghosttyColorDidChange(_ notification: SwiftUI.Notification) {
+            guard let change = notification.userInfo?[
+                SwiftUI.Notification.Name.GhosttyColorChangeKey
+            ] as? Ghostty.Action.ColorChange else { return }
+
+            switch (change.kind) {
+            case .background:
+                self.backgroundColor = change.color
+
+            default:
+                // We don't do anything for the other colors yet.
+                break
+            }
+        }
+
         @objc private func windowDidChangeScreen(notification: SwiftUI.Notification) {
             guard let window = self.window else { return }
             guard let object = notification.object as? NSWindow, window == object else { return }
@@ -1025,6 +1074,27 @@ extension Ghostty {
                 Ghostty.moveFocus(to: self)
             }
         }
+
+        struct DerivedConfig {
+            let backgroundColor: Color
+            let backgroundOpacity: Double
+            let macosWindowShadow: Bool
+            let windowTitleFontFamily: String?
+
+            init() {
+                self.backgroundColor = Color(NSColor.windowBackgroundColor)
+                self.backgroundOpacity = 1
+                self.macosWindowShadow = true
+                self.windowTitleFontFamily = nil
+            }
+
+            init(_ config: Ghostty.Config) {
+                self.backgroundColor = config.backgroundColor
+                self.backgroundOpacity = config.backgroundOpacity
+                self.macosWindowShadow = config.macosWindowShadow
+                self.windowTitleFontFamily = config.windowTitleFontFamily
+            }
+        }
     }
 }
 

macos/Sources/Helpers/OSColor+Extension.swift

@@ -21,6 +21,14 @@ extension OSColor {
         return (0.299 * r) + (0.587 * g) + (0.114 * b)
     }
 
+    var hexString: String? {
+        guard let rgb = usingColorSpace(.deviceRGB) else { return nil }
+        let red = Int(rgb.redComponent * 255)
+        let green = Int(rgb.greenComponent * 255)
+        let blue = Int(rgb.blueComponent * 255)
+        return String(format: "#%02X%02X%02X", red, green, blue)
+    }
+
     func darken(by amount: CGFloat) -> OSColor {
         var h: CGFloat = 0, s: CGFloat = 0, b: CGFloat = 0, a: CGFloat = 0
         self.getHue(&h, saturation: &s, brightness: &b, alpha: &a)

src/App.zig

@@ -147,11 +147,18 @@ pub fn tick(self: *App, rt_app: *apprt.App) !bool {
 /// Update the configuration associated with the app. This can only be
 /// called from the main thread. The caller owns the config memory. The
 /// memory can be freed immediately when this returns.
-pub fn updateConfig(self: *App, config: *const Config) !void {
+pub fn updateConfig(self: *App, rt_app: *apprt.App, config: *const Config) !void {
     // Go through and update all of the surface configurations.
     for (self.surfaces.items) |surface| {
         try surface.core_surface.handleMessage(.{ .change_config = config });
     }
+
+    // Notify the apprt that the app has changed configuration.
+    try rt_app.performAction(
+        .app,
+        .config_change,
+        .{ .config = config },
+    );
 }
 
 /// Add an initialized surface. This is really only for the runtime
@@ -257,7 +264,7 @@ pub fn reloadConfig(self: *App, rt_app: *apprt.App) !void {
     log.debug("reloading configuration", .{});
     if (try rt_app.reloadConfig()) |new| {
         log.debug("new configuration received, applying", .{});
-        try self.updateConfig(new);
+        try self.updateConfig(rt_app, new);
     }
 }
 

src/Surface.zig

@@ -1127,6 +1127,13 @@ pub fn updateConfig(
     self.queueRender() catch |err| {
         log.warn("failed to notify renderer of config change err={}", .{err});
     };
+
+    // Notify the window
+    try self.rt_app.performAction(
+        .{ .surface = self },
+        .config_change,
+        .{ .config = config },
+    );
 }
 
 /// Returns true if the terminal has a selection.

src/apprt/action.zig

@@ -1,6 +1,7 @@
 const std = @import("std");
 const assert = std.debug.assert;
 const apprt = @import("../apprt.zig");
+const configpkg = @import("../config.zig");
 const input = @import("../input.zig");
 const renderer = @import("../renderer.zig");
 const terminal = @import("../terminal/main.zig");
@@ -200,6 +201,20 @@ pub const Action = union(Key) {
     /// on the app or surface.
     config_change_conditional_state,
 
+    /// The configuration has changed. The value is a pointer to the new
+    /// configuration. The pointer is only valid for the duration of the
+    /// action and should not be stored.
+    ///
+    /// This should be used by apprts to update any internal state that
+    /// depends on configuration for the given target (i.e. headerbar colors).
+    /// The apprt should copy any data it needs since the memory lifetime
+    /// is only valid for the duration of the action.
+    ///
+    /// This allows an apprt to have config-dependent state reactively
+    /// change without having to store the entire configuration or poll
+    /// for changes.
+    config_change: ConfigChange,
+
     /// Sync with: ghostty_action_tag_e
     pub const Key = enum(c_int) {
         new_window,
@@ -236,6 +251,7 @@ pub const Action = union(Key) {
         key_sequence,
         color_change,
         config_change_conditional_state,
+        config_change,
     };
 
     /// Sync with: ghostty_action_u
@@ -497,3 +513,18 @@ pub const ColorKind = enum(c_int) {
     // 0+ values indicate a palette index
     _,
 };
+
+pub const ConfigChange = struct {
+    config: *const configpkg.Config,
+
+    // Sync with: ghostty_action_config_change_s
+    pub const C = extern struct {
+        config: *const configpkg.Config,
+    };
+
+    pub fn cval(self: ConfigChange) C {
+        return .{
+            .config = self.config,
+        };
+    }
+};

src/apprt/glfw.zig

@@ -226,6 +226,7 @@ pub const App = struct {
             .color_change,
             .pwd,
             .config_change_conditional_state,
+            .config_change,
             => log.info("unimplemented action={}", .{action}),
         }
     }

src/apprt/gtk/App.zig

@@ -488,6 +488,7 @@ pub fn performAction(
         .render_inspector,
         .renderer_health,
         .color_change,
+        .config_change,
         => log.warn("unimplemented action={}", .{action}),
     }
 }

src/config/CAPI.zig

@@ -19,6 +19,7 @@ export fn ghostty_config_new() ?*Config {
 
     result.* = Config.default(global.alloc) catch |err| {
         log.err("error creating config err={}", .{err});
+        global.alloc.destroy(result);
         return null;
     };
 
@@ -32,6 +33,22 @@ export fn ghostty_config_free(ptr: ?*Config) void {
     }
 }
 
+/// Deep clone the configuration.
+export fn ghostty_config_clone(self: *Config) ?*Config {
+    const result = global.alloc.create(Config) catch |err| {
+        log.err("error allocating config err={}", .{err});
+        return null;
+    };
+
+    result.* = self.clone(global.alloc) catch |err| {
+        log.err("error cloning config err={}", .{err});
+        global.alloc.destroy(result);
+        return null;
+    };
+
+    return result;
+}
+
 /// Load the configuration from the CLI args.
 export fn ghostty_config_load_cli_args(self: *Config) void {
     self.loadCliArgs(global.alloc) catch |err| {

src/config/Config.zig

@@ -365,7 +365,6 @@ const c = @cImport({
 /// be fixed in a future update:
 ///
 ///   - macOS: titlebar tabs style is not updated when switching themes.
-///   - macOS: native titlebar style is not supported.
 ///
 theme: ?Theme = null,
 
@@ -1519,6 +1518,13 @@ keybind: Keybinds = .{},
 /// This makes a more seamless window appearance but looks a little less
 /// typical for a macOS application and may not work well with all themes.
 ///
+/// The "transparent" style will also update in real-time to dynamic
+/// changes to the window background color, i.e. via OSC 11. To make this
+/// more aesthetically pleasing, this only happens if the terminal is
+/// a window, tab, or split that borders the top of the window. This
+/// avoids a disjointed appearance where the titlebar color changes
+/// but all the topmost terminals don't match.
+///
 /// The "tabs" style is a completely custom titlebar that integrates the
 /// tab bar into the titlebar. This titlebar always matches the background
 /// color of the terminal. There are some limitations to this style:
@@ -1537,11 +1543,6 @@ keybind: Keybinds = .{},
 /// but its one I think is the most aesthetically pleasing and works in
 /// most cases.
 ///
-/// BUG: If a separate light/dark mode theme is configured with "theme",
-/// then `macos-titlebar-style = transparent` will not work correctly. To
-/// avoid ugly titlebars, `macos-titlebar-style` will become `native` if
-/// a separate light/dark theme is configured.
-///
 /// Changing this option at runtime only applies to new windows.
 @"macos-titlebar-style": MacTitlebarStyle = .transparent,
 
@@ -2756,12 +2757,6 @@ pub fn finalize(self: *Config) !void {
             // This setting doesn't make sense with different light/dark themes
             // because it'll force the theme based on the Ghostty theme.
             if (self.@"window-theme" == .auto) self.@"window-theme" = .system;
-
-            // This is buggy with different light/dark themes and is noted
-            // in the documentation.
-            if (self.@"macos-titlebar-style" == .transparent) {
-                self.@"macos-titlebar-style" = .native;
-            }
         }
     }