Use foreground color in macOS tab titles

Currently tab titles will use the default macOS tab foreground color,
but the color schemes background color. This can result in tabs with
unreadable text.

This change updates the macOS UI tabs to use the foreground color
defined in the config, or the overridden value when set dynamically.

This change:

- Tracks `foregroundColor` in the SurfaceView which is pre-populated
  with the config foreground color along with support for color change
  update events.
- Adds a new `titleForegroundColor` property to use in `TerminalWindow`
  titles.
- Updates each tab window foreground color when `syncAppearance` is
  called.
- Calls `syncAppearance` when a window becomes the key window.

macos/Sources/Features/Terminal/TerminalController.swift

@@ -253,20 +253,25 @@ class TerminalController: BaseTerminalController {
         // If it does, we match the focused surface. If it doesn't, we use the app
         // configuration.
         let backgroundColor: OSColor
+        let foregroundColor: OSColor
         if let surfaceTree {
             if let focusedSurface, surfaceTree.doesBorderTop(view: focusedSurface) {
                 // Similar to above, an alpha component of "0" causes compositor issues, so
                 // we use 0.001. See: https://github.com/ghostty-org/ghostty/pull/4308
                 backgroundColor = OSColor(focusedSurface.backgroundColor ?? surfaceConfig.backgroundColor).withAlphaComponent(0.001)
+                foregroundColor = OSColor(focusedSurface.foregroundColor ?? surfaceConfig.foregroundColor)
             } 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)
+                foregroundColor = OSColor(surfaceTree.topLeft().foregroundColor ?? derivedConfig.foregroundColor)
             }
         } else {
             backgroundColor = OSColor(self.derivedConfig.backgroundColor)
+            foregroundColor = OSColor(self.derivedConfig.foregroundColor)
         }
         window.titlebarColor = backgroundColor.withAlphaComponent(surfaceConfig.backgroundOpacity)
+        window.titleForegroundColor = foregroundColor
 
         if (window.isOpaque) {
             // Bg color is only synced if we have no transparency. This is because
@@ -278,6 +283,11 @@ class TerminalController: BaseTerminalController {
             // so we only call this if we are opaque.
             window.updateTabBar()
         }
+
+        guard let windows = self.window?.tabbedWindows as? [TerminalWindow] else { return }
+        for (w) in windows {
+            w.titleForegroundColor = window.titleForegroundColor
+        }
     }
 
     private func setInitialWindowPosition(x: Int16?, y: Int16?, windowDecorations: Bool) {
@@ -315,28 +325,28 @@ class TerminalController: BaseTerminalController {
         window.styleMask = [
             // We need `titled` in the mask to get the normal window frame
             .titled,
-            
+
             // Full size content view so we can extend
             // content in to the hidden titlebar's area
                 .fullSizeContentView,
-            
+
                 .resizable,
             .closable,
             .miniaturizable,
         ]
-        
+
         // Hide the title
         window.titleVisibility = .hidden
         window.titlebarAppearsTransparent = true
-        
+
         // Hide the traffic lights (window control buttons)
         window.standardWindowButton(.closeButton)?.isHidden = true
         window.standardWindowButton(.miniaturizeButton)?.isHidden = true
         window.standardWindowButton(.zoomButton)?.isHidden = true
-        
+
         // Disallow tabbing if the titlebar is hidden, since that will (should) also hide the tab bar.
         window.tabbingMode = .disallowed
-        
+
         // Nuke it from orbit -- hide the titlebar container entirely, just in case. There are
         // some operations that appear to bring back the titlebar visibility so this ensures
         // it is gone forever.
@@ -345,7 +355,7 @@ class TerminalController: BaseTerminalController {
             titleBarContainer.isHidden = true
         }
     }
-    
+
     override func windowDidLoad() {
         super.windowDidLoad()
         guard let window = window as? TerminalWindow else { return }
@@ -429,6 +439,7 @@ class TerminalController: BaseTerminalController {
 
             // This makes sure our titlebar renders correctly when there is a transparent background
             window.titlebarColor = backgroundColor.withAlphaComponent(config.backgroundOpacity)
+            window.titleForegroundColor = NSColor(config.foregroundColor)
         }
 
         // Initialize our content view to the SwiftUI root
@@ -487,6 +498,10 @@ class TerminalController: BaseTerminalController {
         super.windowDidBecomeKey(notification)
         self.relabelTabs()
         self.fixTabBar()
+
+        if let focusedSurface {
+            self.syncAppearance(focusedSurface.derivedConfig)
+        }
     }
 
     override func windowDidMove(_ notification: Notification) {
@@ -651,6 +666,9 @@ class TerminalController: BaseTerminalController {
         focusedSurface.$backgroundColor
             .sink { [weak self, weak focusedSurface] _ in self?.syncAppearanceOnPropertyChange(focusedSurface) }
             .store(in: &surfaceAppearanceCancellables)
+        focusedSurface.$foregroundColor
+            .sink { [weak self, weak focusedSurface] _ in self?.syncAppearanceOnPropertyChange(focusedSurface) }
+            .store(in: &surfaceAppearanceCancellables)
     }
 
     private func syncAppearanceOnPropertyChange(_ surface: Ghostty.SurfaceView?) {
@@ -780,15 +798,18 @@ class TerminalController: BaseTerminalController {
 
     private struct DerivedConfig {
         let backgroundColor: Color
+        let foregroundColor: Color
         let macosTitlebarStyle: String
 
         init() {
             self.backgroundColor = Color(NSColor.windowBackgroundColor)
+            self.foregroundColor = Color(NSColor.labelColor)
             self.macosTitlebarStyle = "system"
         }
 
         init(_ config: Ghostty.Config) {
             self.backgroundColor = config.backgroundColor
+            self.foregroundColor = config.foregroundColor
             self.macosTitlebarStyle = config.macosTitlebarStyle
         }
     }

macos/Sources/Features/Terminal/TerminalToolbar.swift

@@ -25,6 +25,16 @@ class TerminalToolbar: NSToolbar, NSToolbarDelegate {
         }
     }
 
+    var titleColor: NSColor? {
+        get {
+            titleTextField.textColor
+        }
+
+        set {
+            titleTextField.textColor = newValue
+        }
+    }
+
     override init(identifier: NSToolbar.Identifier) {
         super.init(identifier: identifier)
 

macos/Sources/Features/Terminal/TerminalWindow.swift

@@ -8,6 +8,17 @@ class TerminalWindow: NSWindow {
             guard let titlebarContainer else { return }
             titlebarContainer.wantsLayer = true
             titlebarContainer.layer?.backgroundColor = titlebarColor.cgColor
+            tab.attributedTitle = attributedTitle
+        }
+    }
+
+    lazy var titleForegroundColor: NSColor = NSColor.labelColor {
+        didSet {
+            tab.attributedTitle = attributedTitle
+            if let toolbar = toolbar as? TerminalToolbar {
+                toolbar.titleColor = titleForegroundColor
+            }
+            self.updateKeyEquivalentLabel()
         }
     }
 
@@ -28,13 +39,7 @@ class TerminalWindow: NSWindow {
         },
 
         observe(\.keyEquivalent, options: [.initial, .new]) { [weak self] window, _ in
-            let attributes: [NSAttributedString.Key: Any] = [
+            self?.updateKeyEquivalentLabel()
-                .font: NSFont.systemFont(ofSize: NSFont.smallSystemFontSize),
-                .foregroundColor: window.isKeyWindow ? NSColor.labelColor : NSColor.secondaryLabelColor,
-            ]
-            let attributedString = NSAttributedString(string: " \(window.keyEquivalent) ", attributes: attributes)
-
-            self?.keyEquivalentLabel.attributedStringValue = attributedString
         },
     ]
 
@@ -317,6 +322,17 @@ class TerminalWindow: NSWindow {
 		}
 	}
 
+    private func updateKeyEquivalentLabel() {
+        let attributes: [NSAttributedString.Key: Any] = [
+            .font: NSFont.systemFont(ofSize: 11),
+            .foregroundColor: self.titleForegroundColor.withAlphaComponent(isKeyWindow ? 1 : 0.4),
+        ]
+        let attributedString = NSAttributedString(string: " \(keyEquivalent) ", attributes: attributes)
+
+        keyEquivalentLabel.attributedStringValue = attributedString
+    }
+
+
     // MARK: - Split Zoom Button
 
     @objc dynamic var surfaceIsZoomed: Bool = false
@@ -403,13 +419,13 @@ class TerminalWindow: NSWindow {
     // Used to set the titlebar font.
     var titlebarFont: NSFont? {
         didSet {
-            let font = titlebarFont ?? NSFont.titleBarFont(ofSize: NSFont.systemFontSize)
+            let font = titlebarFont ?? NSFont.titleBarFont(ofSize: 11)
 
             titlebarTextField?.font = font
             tab.attributedTitle = attributedTitle
 
             if let toolbar = toolbar as? TerminalToolbar {
-                toolbar.titleFont = font
+                toolbar.titleFont = font.withSize(NSFont.systemFontSize)
             }
         }
     }
@@ -423,12 +439,11 @@ class TerminalWindow: NSWindow {
 
     // Return a styled representation of our title property.
     private var attributedTitle: NSAttributedString? {
-        guard let titlebarFont else { return nil }
-
         let attributes: [NSAttributedString.Key: Any] = [
-            .font: titlebarFont,
+            .foregroundColor: titleForegroundColor,
-            .foregroundColor: isKeyWindow ? NSColor.labelColor : NSColor.secondaryLabelColor,
+            .font: titlebarFont?.withSize(11) ?? NSFont.systemFont(ofSize: 11),
         ]
+
         return NSAttributedString(string: title, attributes: attributes)
     }
 

macos/Sources/Ghostty/Ghostty.Config.swift

@@ -350,6 +350,26 @@ extension Ghostty {
             return v;
         }
 
+        var foregroundColor: Color {
+            var color: ghostty_config_color_s = .init();
+            let bg_key = "foreground"
+            if (!ghostty_config_get(config, &color, bg_key, UInt(bg_key.count))) {
+#if os(macOS)
+                return Color(NSColor.labelColor)
+#elseif os(iOS)
+                return Color(UIColor.label)
+#else
+#error("unsupported")
+#endif
+            }
+
+            return .init(
+                red: Double(color.r) / 255,
+                green: Double(color.g) / 255,
+                blue: Double(color.b) / 255
+            )
+        }
+
         var unfocusedSplitOpacity: Double {
             guard let config = self.config else { return 1 }
             var opacity: Double = 0.85

macos/Sources/Ghostty/SurfaceView_AppKit.swift

@@ -55,6 +55,10 @@ extension Ghostty {
         /// dynamically updated. Otherwise, the background color is the default background color.
         @Published private(set) var backgroundColor: Color? = nil
 
+        /// The foreground 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 foregroundColor: 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
@@ -443,6 +447,11 @@ extension Ghostty {
                 DispatchQueue.main.async { [weak self] in
                     self?.backgroundColor = change.color
                 }
+                self.backgroundColor = change.color
+            case .foreground:
+                DispatchQueue.main.async { [weak self] in
+                    self?.foregroundColor = change.color
+                }
 
             default:
                 // We don't do anything for the other colors yet.
@@ -1209,6 +1218,7 @@ extension Ghostty {
         struct DerivedConfig {
             let backgroundColor: Color
             let backgroundOpacity: Double
+            let foregroundColor: Color
             let macosWindowShadow: Bool
             let windowTitleFontFamily: String?
             let windowAppearance: NSAppearance?
@@ -1216,6 +1226,7 @@ extension Ghostty {
             init() {
                 self.backgroundColor = Color(NSColor.windowBackgroundColor)
                 self.backgroundOpacity = 1
+                self.foregroundColor = Color(NSColor.labelColor)
                 self.macosWindowShadow = true
                 self.windowTitleFontFamily = nil
                 self.windowAppearance = nil
@@ -1224,6 +1235,7 @@ extension Ghostty {
             init(_ config: Ghostty.Config) {
                 self.backgroundColor = config.backgroundColor
                 self.backgroundOpacity = config.backgroundOpacity
+                self.foregroundColor = config.foregroundColor
                 self.macosWindowShadow = config.macosWindowShadow
                 self.windowTitleFontFamily = config.windowTitleFontFamily
                 self.windowAppearance = .init(ghosttyConfig: config)