diff --git a/index.html b/index.html
index ff93803bb..3d0c8aaf3 100644
--- a/index.html
+++ b/index.html
@@ -4,6 +4,7 @@
     <meta charset="UTF-8" />
     <link rel="icon" type="image/svg+xml" href="/vite.svg" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <meta name="color-scheme" content="light dark" />
     <title>Tauri + React + Typescript</title>
   </head>
 
diff --git a/src-tauri/Cargo.lock b/src-tauri/Cargo.lock
index 350844423..ddb75cff4 100644
--- a/src-tauri/Cargo.lock
+++ b/src-tauri/Cargo.lock
@@ -572,6 +572,8 @@ dependencies = [
  "git2",
  "ignore",
  "libc",
+ "objc2-app-kit",
+ "objc2-foundation",
  "portable-pty",
  "reqwest",
  "serde",
diff --git a/src-tauri/Cargo.toml b/src-tauri/Cargo.toml
index 2a12fcabb..35548c275 100644
--- a/src-tauri/Cargo.toml
+++ b/src-tauri/Cargo.toml
@@ -42,3 +42,7 @@ tauri-plugin-updater = "2"
 cpal = "0.15"
 whisper-rs = "0.12"
 sha2 = "0.10"
+
+[target."cfg(target_os = \"macos\")".dependencies]
+objc2-app-kit = { version = "0.3", features = ["NSAppearance", "NSResponder", "NSWindow"] }
+objc2-foundation = { version = "0.3", features = ["NSString"] }
diff --git a/src-tauri/src/bin/codex_monitor_daemon.rs b/src-tauri/src/bin/codex_monitor_daemon.rs
index 21ffa92ac..541f88acc 100644
--- a/src-tauri/src/bin/codex_monitor_daemon.rs
+++ b/src-tauri/src/bin/codex_monitor_daemon.rs
@@ -1,3 +1,4 @@
+#[allow(dead_code)]
 #[path = "../backend/mod.rs"]
 mod backend;
 #[path = "../codex_home.rs"]
@@ -8,6 +9,7 @@ mod codex_config;
 mod rules;
 #[path = "../storage.rs"]
 mod storage;
+#[allow(dead_code)]
 #[path = "../types.rs"]
 mod types;
 
@@ -42,6 +44,7 @@ struct DaemonEventSink {
 #[derive(Clone)]
 enum DaemonEvent {
     AppServer(AppServerEvent),
+    #[allow(dead_code)]
     TerminalOutput(TerminalOutput),
 }
 
@@ -1088,13 +1091,6 @@ fn parse_optional_u32(value: &Value, key: &str) -> Option<u32> {
     }
 }
 
-fn parse_optional_bool(value: &Value, key: &str) -> Option<bool> {
-    match value {
-        Value::Object(map) => map.get(key).and_then(|value| value.as_bool()),
-        _ => None,
-    }
-}
-
 fn parse_optional_string_array(value: &Value, key: &str) -> Option<Vec<String>> {
     match value {
         Value::Object(map) => map.get(key).and_then(|value| value.as_array()).map(|items| {
diff --git a/src-tauri/src/lib.rs b/src-tauri/src/lib.rs
index f11f02b2e..dc3b23dda 100644
--- a/src-tauri/src/lib.rs
+++ b/src-tauri/src/lib.rs
@@ -20,6 +20,7 @@ mod rules;
 mod settings;
 mod state;
 mod terminal;
+mod window;
 mod storage;
 mod types;
 mod utils;
diff --git a/src-tauri/src/settings.rs b/src-tauri/src/settings.rs
index 5a576ae40..9bce0693f 100644
--- a/src-tauri/src/settings.rs
+++ b/src-tauri/src/settings.rs
@@ -1,12 +1,16 @@
-use tauri::State;
+use tauri::{State, Window};
 
 use crate::codex_config;
 use crate::state::AppState;
 use crate::storage::write_settings;
 use crate::types::AppSettings;
+use crate::window;
 
 #[tauri::command]
-pub(crate) async fn get_app_settings(state: State<'_, AppState>) -> Result<AppSettings, String> {
+pub(crate) async fn get_app_settings(
+    state: State<'_, AppState>,
+    window: Window,
+) -> Result<AppSettings, String> {
     let mut settings = state.app_settings.lock().await.clone();
     if let Ok(Some(collab_enabled)) = codex_config::read_collab_enabled() {
         settings.experimental_collab_enabled = collab_enabled;
@@ -17,6 +21,7 @@ pub(crate) async fn get_app_settings(state: State<'_, AppState>) -> Result<AppSe
     if let Ok(Some(unified_exec_enabled)) = codex_config::read_unified_exec_enabled() {
         settings.experimental_unified_exec_enabled = unified_exec_enabled;
     }
+    let _ = window::apply_window_appearance(&window, settings.theme.as_str());
     Ok(settings)
 }
 
@@ -24,6 +29,7 @@ pub(crate) async fn get_app_settings(state: State<'_, AppState>) -> Result<AppSe
 pub(crate) async fn update_app_settings(
     settings: AppSettings,
     state: State<'_, AppState>,
+    window: Window,
 ) -> Result<AppSettings, String> {
     let _ = codex_config::write_collab_enabled(settings.experimental_collab_enabled);
     let _ = codex_config::write_steer_enabled(settings.experimental_steer_enabled);
@@ -31,5 +37,6 @@ pub(crate) async fn update_app_settings(
     write_settings(&state.settings_path, &settings)?;
     let mut current = state.app_settings.lock().await;
     *current = settings.clone();
+    let _ = window::apply_window_appearance(&window, settings.theme.as_str());
     Ok(settings)
 }
diff --git a/src-tauri/src/types.rs b/src-tauri/src/types.rs
index be9127f1c..0f391c499 100644
--- a/src-tauri/src/types.rs
+++ b/src-tauri/src/types.rs
@@ -262,6 +262,8 @@ pub(crate) struct AppSettings {
     pub(crate) last_composer_reasoning_effort: Option<String>,
     #[serde(default = "default_ui_scale", rename = "uiScale")]
     pub(crate) ui_scale: f64,
+    #[serde(default = "default_theme", rename = "theme")]
+    pub(crate) theme: String,
     #[serde(
         default = "default_notification_sounds_enabled",
         rename = "notificationSoundsEnabled"
@@ -325,6 +327,10 @@ fn default_ui_scale() -> f64 {
     1.0
 }
 
+fn default_theme() -> String {
+    "system".to_string()
+}
+
 fn default_composer_model_shortcut() -> Option<String> {
     Some("cmd+shift+m".to_string())
 }
@@ -383,6 +389,7 @@ impl Default for AppSettings {
             last_composer_model_id: None,
             last_composer_reasoning_effort: None,
             ui_scale: 1.0,
+            theme: default_theme(),
             notification_sounds_enabled: true,
             experimental_collab_enabled: false,
             experimental_steer_enabled: false,
@@ -425,6 +432,7 @@ mod tests {
         assert!(settings.last_composer_model_id.is_none());
         assert!(settings.last_composer_reasoning_effort.is_none());
         assert!((settings.ui_scale - 1.0).abs() < f64::EPSILON);
+        assert_eq!(settings.theme, "system");
         assert!(settings.notification_sounds_enabled);
         assert!(!settings.experimental_steer_enabled);
         assert!(!settings.dictation_enabled);
diff --git a/src-tauri/src/window.rs b/src-tauri/src/window.rs
new file mode 100644
index 000000000..17b2bf1d6
--- /dev/null
+++ b/src-tauri/src/window.rs
@@ -0,0 +1,53 @@
+use tauri::{Theme, Window};
+
+#[cfg(target_os = "macos")]
+fn apply_macos_window_appearance(window: &Window, theme: &str) -> Result<(), String> {
+    use objc2_app_kit::{
+        NSAppearance, NSAppearanceCustomization, NSAppearanceNameAqua,
+        NSAppearanceNameDarkAqua, NSWindow,
+    };
+
+    let ns_window = window
+        .ns_window()
+        .map_err(|error| error.to_string())?;
+    let ns_window: &NSWindow = unsafe { &*ns_window.cast() };
+
+    if theme == "system" {
+        ns_window.setAppearance(None);
+        return Ok(());
+    }
+
+    let appearance_name = unsafe {
+        if theme == "dark" {
+            NSAppearanceNameDarkAqua
+        } else {
+            NSAppearanceNameAqua
+        }
+    };
+    let appearance =
+        NSAppearance::appearanceNamed(appearance_name).ok_or("NSAppearance missing")?;
+    ns_window.setAppearance(Some(&appearance));
+    Ok(())
+}
+
+pub(crate) fn apply_window_appearance(window: &Window, theme: &str) -> Result<(), String> {
+    let next_theme = match theme {
+        "light" => Some(Theme::Light),
+        "dark" => Some(Theme::Dark),
+        _ => None,
+    };
+    let _ = window.set_theme(next_theme);
+
+    #[cfg(target_os = "macos")]
+    {
+        let window_handle = window.clone();
+        let theme_value = theme.to_string();
+        window
+            .run_on_main_thread(move || {
+                let _ = apply_macos_window_appearance(&window_handle, theme_value.as_str());
+            })
+            .map_err(|error| error.to_string())?;
+    }
+
+    Ok(())
+}
diff --git a/src/App.tsx b/src/App.tsx
index 5a28a6e31..e3e8c7421 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -61,6 +61,7 @@ import { useResizablePanels } from "./features/layout/hooks/useResizablePanels";
 import { useLayoutMode } from "./features/layout/hooks/useLayoutMode";
 import { useSidebarToggles } from "./features/layout/hooks/useSidebarToggles";
 import { useTransparencyPreference } from "./features/layout/hooks/useTransparencyPreference";
+import { useThemePreference } from "./features/layout/hooks/useThemePreference";
 import { useWindowLabel } from "./features/layout/hooks/useWindowLabel";
 import { revealItemInDir } from "@tauri-apps/plugin-opener";
 import {
@@ -107,6 +108,7 @@ function MainApp() {
     doctor,
     isLoading: appSettingsLoading
   } = useAppSettings();
+  useThemePreference(appSettings.theme);
   const dictationModel = useDictationModel(appSettings.dictationModelId);
   const {
     state: dictationState,
diff --git a/src/features/layout/hooks/useThemePreference.ts b/src/features/layout/hooks/useThemePreference.ts
new file mode 100644
index 000000000..bfdf94c27
--- /dev/null
+++ b/src/features/layout/hooks/useThemePreference.ts
@@ -0,0 +1,13 @@
+import { useEffect } from "react";
+import type { ThemePreference } from "../../../types";
+
+export function useThemePreference(theme: ThemePreference) {
+  useEffect(() => {
+    const root = document.documentElement;
+    if (theme === "system") {
+      delete root.dataset.theme;
+      return;
+    }
+    root.dataset.theme = theme;
+  }, [theme]);
+}
diff --git a/src/features/settings/components/SettingsView.tsx b/src/features/settings/components/SettingsView.tsx
index 14152e463..8199adb13 100644
--- a/src/features/settings/components/SettingsView.tsx
+++ b/src/features/settings/components/SettingsView.tsx
@@ -718,6 +718,26 @@ export function SettingsView({
                 <div className="settings-subsection-subtitle">
                   Adjust how the window renders backgrounds and effects.
                 </div>
+                <div className="settings-field">
+                  <label className="settings-field-label" htmlFor="theme-select">
+                    Theme
+                  </label>
+                  <select
+                    id="theme-select"
+                    className="settings-select"
+                    value={appSettings.theme}
+                    onChange={(event) =>
+                      void onUpdateAppSettings({
+                        ...appSettings,
+                        theme: event.target.value as AppSettings["theme"],
+                      })
+                    }
+                  >
+                    <option value="system">System</option>
+                    <option value="light">Light</option>
+                    <option value="dark">Dark</option>
+                  </select>
+                </div>
                 <div className="settings-toggle-row">
                   <div>
                     <div className="settings-toggle-title">Reduce transparency</div>
diff --git a/src/features/settings/hooks/useAppSettings.ts b/src/features/settings/hooks/useAppSettings.ts
index 85a48882c..a660fd7e7 100644
--- a/src/features/settings/hooks/useAppSettings.ts
+++ b/src/features/settings/hooks/useAppSettings.ts
@@ -3,6 +3,8 @@ import type { AppSettings } from "../../../types";
 import { getAppSettings, runCodexDoctor, updateAppSettings } from "../../../services/tauri";
 import { clampUiScale, UI_SCALE_DEFAULT } from "../../../utils/uiScale";
 
+const allowedThemes = new Set(["system", "light", "dark"]);
+
 const defaultSettings: AppSettings = {
   codexBin: null,
   backendMode: "local",
@@ -15,6 +17,7 @@ const defaultSettings: AppSettings = {
   lastComposerModelId: null,
   lastComposerReasoningEffort: null,
   uiScale: UI_SCALE_DEFAULT,
+  theme: "system",
   notificationSoundsEnabled: true,
   experimentalCollabEnabled: false,
   experimentalSteerEnabled: false,
@@ -30,6 +33,7 @@ function normalizeAppSettings(settings: AppSettings): AppSettings {
   return {
     ...settings,
     uiScale: clampUiScale(settings.uiScale),
+    theme: allowedThemes.has(settings.theme) ? settings.theme : "system",
   };
 }
 
diff --git a/src/styles/base.css b/src/styles/base.css
index 13f12b09a..211ff4efa 100644
--- a/src/styles/base.css
+++ b/src/styles/base.css
@@ -70,6 +70,10 @@
   --ui-scale: 1;
 }
 
+:root[data-theme="dark"] {
+  color-scheme: dark;
+}
+
 .app.reduced-transparency {
   --surface-sidebar: rgba(18, 18, 18, 0.92);
   --surface-topbar: rgba(10, 14, 20, 0.94);
@@ -95,8 +99,90 @@
   --surface-popover: rgba(16, 20, 30, 0.995);
 }
 
-  @media (prefers-color-scheme: light) {
-  :root {
+:root[data-theme="light"] {
+  color-scheme: light;
+  --text-primary: #1a1d24;
+  --text-strong: #0e1118;
+  --text-emphasis: rgba(17, 20, 28, 0.9);
+  --text-stronger: rgba(17, 20, 28, 0.85);
+  --text-quiet: rgba(17, 20, 28, 0.75);
+  --text-muted: rgba(17, 20, 28, 0.7);
+  --text-subtle: rgba(17, 20, 28, 0.6);
+  --text-faint: rgba(17, 20, 28, 0.5);
+  --text-fainter: rgba(17, 20, 28, 0.45);
+  --text-dim: rgba(17, 20, 28, 0.35);
+  --surface-sidebar: rgba(246, 247, 250, 0.82);
+  --surface-topbar: rgba(250, 251, 253, 0.9);
+  --surface-right-panel: rgba(245, 247, 250, 0.82);
+  --surface-composer: rgba(250, 251, 253, 0.9);
+  --surface-messages: rgba(238, 241, 246, 0.9);
+  --surface-card: rgba(255, 255, 255, 0.72);
+  --surface-card-strong: rgba(255, 255, 255, 0.92);
+  --surface-card-muted: rgba(255, 255, 255, 0.7);
+  --surface-item: rgba(255, 255, 255, 0.6);
+  --surface-control: rgba(15, 23, 36, 0.08);
+  --surface-control-hover: rgba(15, 23, 36, 0.12);
+  --surface-control-disabled: rgba(15, 23, 36, 0.05);
+  --surface-hover: rgba(15, 23, 36, 0.06);
+  --surface-active: rgba(77, 153, 255, 0.18);
+  --surface-approval: rgba(246, 248, 252, 0.92);
+  --surface-debug: rgba(242, 244, 248, 0.9);
+  --surface-command: rgba(245, 247, 250, 0.95);
+  --surface-diff-card: rgba(240, 243, 248, 0.92);
+  --surface-bubble: rgba(255, 255, 255, 0.9);
+  --surface-bubble-user: rgba(77, 153, 255, 0.22);
+  --surface-context-core: rgba(255, 255, 255, 0.9);
+  --surface-popover: rgba(255, 255, 255, 0.99);
+  --surface-review: rgba(255, 170, 210, 0.25);
+  --border-review: rgba(200, 90, 140, 0.45);
+  --surface-review-active: rgba(255, 170, 210, 0.32);
+  --text-review-active: rgba(120, 30, 70, 0.9);
+  --surface-review-done: rgba(140, 235, 200, 0.35);
+  --text-review-done: rgba(20, 90, 60, 0.9);
+  --border-subtle: rgba(15, 23, 36, 0.08);
+  --border-muted: rgba(15, 23, 36, 0.06);
+  --border-strong: rgba(15, 23, 36, 0.14);
+  --border-stronger: rgba(15, 23, 36, 0.18);
+  --border-quiet: rgba(15, 23, 36, 0.2);
+  --border-accent: rgba(77, 153, 255, 0.5);
+  --border-accent-soft: rgba(77, 153, 255, 0.28);
+  --text-accent: rgba(45, 93, 170, 0.7);
+  --shadow-accent: rgba(90, 140, 210, 0.18);
+  --status-success: rgba(30, 155, 110, 0.9);
+  --status-warning: rgba(215, 120, 20, 0.9);
+  --status-error: rgba(200, 45, 45, 0.9);
+  --status-unknown: rgba(17, 20, 28, 0.25);
+  --select-caret: rgba(15, 23, 36, 0.45);
+}
+
+:root[data-theme="light"] .app.reduced-transparency {
+  --surface-sidebar: rgba(240, 242, 247, 0.98);
+  --surface-topbar: rgba(244, 246, 250, 0.98);
+  --surface-right-panel: rgba(242, 244, 248, 0.98);
+  --surface-composer: rgba(244, 246, 250, 0.98);
+  --surface-messages: rgba(240, 242, 247, 0.98);
+  --surface-card: rgba(255, 255, 255, 0.96);
+  --surface-card-strong: rgba(255, 255, 255, 0.98);
+  --surface-card-muted: rgba(252, 253, 255, 0.96);
+  --surface-item: rgba(250, 251, 253, 0.96);
+  --surface-control: rgba(15, 23, 36, 0.12);
+  --surface-control-hover: rgba(15, 23, 36, 0.18);
+  --surface-control-disabled: rgba(15, 23, 36, 0.08);
+  --surface-hover: rgba(15, 23, 36, 0.1);
+  --surface-active: rgba(77, 153, 255, 0.22);
+  --surface-approval: rgba(248, 249, 252, 0.98);
+  --surface-debug: rgba(246, 248, 252, 0.98);
+  --surface-command: rgba(250, 251, 253, 0.98);
+  --surface-diff-card: rgba(244, 246, 250, 0.98);
+  --surface-bubble: rgba(255, 255, 255, 0.98);
+  --surface-bubble-user: rgba(77, 153, 255, 0.28);
+  --surface-context-core: rgba(255, 255, 255, 0.98);
+  --surface-popover: rgba(255, 255, 255, 0.995);
+}
+
+@media (prefers-color-scheme: light) {
+  :root:not([data-theme]) {
+    color-scheme: light;
     --text-primary: #1a1d24;
     --text-strong: #0e1118;
     --text-emphasis: rgba(17, 20, 28, 0.9);
@@ -118,23 +204,23 @@
     --surface-item: rgba(255, 255, 255, 0.6);
     --surface-control: rgba(15, 23, 36, 0.08);
     --surface-control-hover: rgba(15, 23, 36, 0.12);
-  --surface-control-disabled: rgba(15, 23, 36, 0.05);
-  --surface-hover: rgba(15, 23, 36, 0.06);
-  --surface-active: rgba(77, 153, 255, 0.18);
+    --surface-control-disabled: rgba(15, 23, 36, 0.05);
+    --surface-hover: rgba(15, 23, 36, 0.06);
+    --surface-active: rgba(77, 153, 255, 0.18);
     --surface-approval: rgba(246, 248, 252, 0.92);
     --surface-debug: rgba(242, 244, 248, 0.9);
     --surface-command: rgba(245, 247, 250, 0.95);
     --surface-diff-card: rgba(240, 243, 248, 0.92);
-  --surface-bubble: rgba(255, 255, 255, 0.9);
-  --surface-bubble-user: rgba(77, 153, 255, 0.22);
-  --surface-context-core: rgba(255, 255, 255, 0.9);
-  --surface-popover: rgba(255, 255, 255, 0.99);
-  --surface-review: rgba(255, 170, 210, 0.25);
-  --border-review: rgba(200, 90, 140, 0.45);
-  --surface-review-active: rgba(255, 170, 210, 0.32);
-  --text-review-active: rgba(120, 30, 70, 0.9);
-  --surface-review-done: rgba(140, 235, 200, 0.35);
-  --text-review-done: rgba(20, 90, 60, 0.9);
+    --surface-bubble: rgba(255, 255, 255, 0.9);
+    --surface-bubble-user: rgba(77, 153, 255, 0.22);
+    --surface-context-core: rgba(255, 255, 255, 0.9);
+    --surface-popover: rgba(255, 255, 255, 0.99);
+    --surface-review: rgba(255, 170, 210, 0.25);
+    --border-review: rgba(200, 90, 140, 0.45);
+    --surface-review-active: rgba(255, 170, 210, 0.32);
+    --text-review-active: rgba(120, 30, 70, 0.9);
+    --surface-review-done: rgba(140, 235, 200, 0.35);
+    --text-review-done: rgba(20, 90, 60, 0.9);
     --border-subtle: rgba(15, 23, 36, 0.08);
     --border-muted: rgba(15, 23, 36, 0.06);
     --border-strong: rgba(15, 23, 36, 0.14);
@@ -142,16 +228,16 @@
     --border-quiet: rgba(15, 23, 36, 0.2);
     --border-accent: rgba(77, 153, 255, 0.5);
     --border-accent-soft: rgba(77, 153, 255, 0.28);
-  --text-accent: rgba(45, 93, 170, 0.7);
-  --shadow-accent: rgba(90, 140, 210, 0.18);
-  --status-success: rgba(30, 155, 110, 0.9);
+    --text-accent: rgba(45, 93, 170, 0.7);
+    --shadow-accent: rgba(90, 140, 210, 0.18);
+    --status-success: rgba(30, 155, 110, 0.9);
     --status-warning: rgba(215, 120, 20, 0.9);
     --status-error: rgba(200, 45, 45, 0.9);
     --status-unknown: rgba(17, 20, 28, 0.25);
-  --select-caret: rgba(15, 23, 36, 0.45);
+    --select-caret: rgba(15, 23, 36, 0.45);
   }
 
-  .app.reduced-transparency {
+  :root:not([data-theme]) .app.reduced-transparency {
     --surface-sidebar: rgba(240, 242, 247, 0.98);
     --surface-topbar: rgba(244, 246, 250, 0.98);
     --surface-right-panel: rgba(242, 244, 248, 0.98);
diff --git a/src/styles/composer.css b/src/styles/composer.css
index 3795fa842..452cdba2b 100644
--- a/src/styles/composer.css
+++ b/src/styles/composer.css
@@ -198,13 +198,22 @@
   position: relative;
 }
 
+:root[data-theme="light"] .composer-action {
+  border-color: var(--border-strong);
+  color: var(--text-strong);
+}
+
+:root[data-theme="light"] .composer-action:hover {
+  color: var(--text-strong);
+}
+
 @media (prefers-color-scheme: light) {
-  .composer-action {
+  :root:not([data-theme]) .composer-action {
     border-color: var(--border-strong);
     color: var(--text-strong);
   }
 
-  .composer-action:hover {
+  :root:not([data-theme]) .composer-action:hover {
     color: var(--text-strong);
   }
 }
diff --git a/src/styles/messages.css b/src/styles/messages.css
index 1da7dd190..3a740c715 100644
--- a/src/styles/messages.css
+++ b/src/styles/messages.css
@@ -73,8 +73,13 @@
   animation: working-shimmer 2.2s ease-in-out infinite;
 }
 
+:root[data-theme="light"] .working-text {
+  color: var(--text-muted);
+  background: none;
+}
+
 @media (prefers-color-scheme: light) {
-  .working-text {
+  :root:not([data-theme]) .working-text {
     color: var(--text-muted);
     background: none;
   }
diff --git a/src/types.ts b/src/types.ts
index aa2d28529..444584dc5 100644
--- a/src/types.ts
+++ b/src/types.ts
@@ -71,6 +71,7 @@ export type ReviewTarget =
 
 export type AccessMode = "read-only" | "current" | "full-access";
 export type BackendMode = "local" | "remote";
+export type ThemePreference = "system" | "light" | "dark";
 
 export type AppSettings = {
   codexBin: string | null;
@@ -84,6 +85,7 @@ export type AppSettings = {
   lastComposerModelId: string | null;
   lastComposerReasoningEffort: string | null;
   uiScale: number;
+  theme: ThemePreference;
   notificationSoundsEnabled: boolean;
   experimentalCollabEnabled: boolean;
   experimentalSteerEnabled: boolean;