Add content protection checkbox to Settings window

_locales/en/messages.json

@@ -6936,6 +6936,30 @@
     "messageformat": "Restart",
     "description": "Button to restart Signal to apply language changes"
   },
+  "icu:Preferences__Privacy__Application": {
+    "messageformat": "Application",
+    "description": "Title of Application section in Settings > Privacy"
+  },
+  "icu:Preferences__content-protection--label": {
+    "messageformat": "Screen security",
+    "description": "Label of checkbox in Settings > Privacy > Application"
+  },
+  "icu:Preferences__content-protection--description": {
+    "messageformat": "Prevent screenshots of Signal on this computer for added privacy.",
+    "description": "Description of checkbox in Settings > Privacy > Application"
+  },
+  "icu:Preferences__content-protection__modal--title": {
+    "messageformat": "Disable screen security?",
+    "description": "Title of confirm disabling screen security modal in Settings > Privacy > Application"
+  },
+  "icu:Preferences__content-protection__modal--body": {
+    "messageformat": "If disabled, this may allow Microsoft Windows to capture screenshots of Signal and use them for features that may not be private.",
+    "description": "Body of confirm disabling screen security modal in Settings > Privacy > Application"
+  },
+  "icu:Preferences__content-protection__modal--disable": {
+    "messageformat": "Disable",
+    "description": "Text of the button confirm disabling screen security modal in Settings > Privacy > Application"
+  },
   "icu:DialogUpdate--version-available": {
     "messageformat": "Update to version {version} available",
     "description": "Tooltip for new update available"

app/main.ts

@@ -571,6 +571,15 @@ async function handleCommonWindowEvents(window: BrowserWindow) {
   const focusInterval = setInterval(setWindowFocus, 10000);
   window.on('closed', () => clearInterval(focusInterval));
 
+  const contentProtection = ephemeralConfig.get('contentProtection');
+  // Apply content protection by default on Windows, unless explicitly disabled
+  // by user in settings.
+  if (contentProtection ?? OS.isWindows()) {
+    window.once('ready-to-show', async () => {
+      window.setContentProtection(true);
+    });
+  }
+
   await zoomFactorService.syncWindow(window);
 
   nativeThemeNotifier.addWindow(window);
@@ -2132,6 +2141,7 @@ app.on('ready', async () => {
     'ephemeral-setting-changed',
     sendPreferencesChangedEventToWindows
   );
+  settingsChannel.on('ephemeral-setting-changed', onEphemeralSettingChanged);
 
   // We use this event only a single time to log the startup time of the app
   // from when it's first ready until the loading screen disappears.
@@ -2902,6 +2912,20 @@ const sendPreferencesChangedEventToWindows = () => {
 };
 ipc.on('preferences-changed', sendPreferencesChangedEventToWindows);
 
+const onEphemeralSettingChanged = (name: string) => {
+  if (name !== 'contentProtection') {
+    return;
+  }
+
+  const contentProtection = ephemeralConfig.get('contentProtection');
+
+  for (const window of activeWindows) {
+    if (typeof contentProtection === 'boolean') {
+      window.setContentProtection(contentProtection);
+    }
+  }
+};
+
 function maybeGetIncomingSignalRoute(argv: Array<string>) {
   for (const arg of argv) {
     const route = parseSignalRoute(arg);

ts/components/Preferences.stories.tsx

@@ -111,6 +111,7 @@ export default {
     hasAutoLaunch: true,
     hasCallNotifications: true,
     hasCallRingtoneNotification: false,
+    hasContentProtection: false,
     hasCountMutedConversations: false,
     hasHideMenuBar: false,
     hasIncomingCallNotifications: true,
@@ -136,6 +137,8 @@ export default {
     isSyncSupported: true,
     isSystemTraySupported: true,
     isInternalUser: false,
+    isContentProtectionSupported: true,
+    isContentProtectionNeeded: true,
     isMinimizeToAndStartInSystemTraySupported: true,
     lastSyncTime: Date.now(),
     localeOverride: null,
@@ -182,6 +185,7 @@ export default {
     onCallRingtoneNotificationChange: action(
       'onCallRingtoneNotificationChange'
     ),
+    onContentProtectionChange: action('onContentProtectionChange'),
     onCountMutedConversationsChange: action('onCountMutedConversationsChange'),
     onEmojiSkinToneDefaultChange: action('onEmojiSkinToneDefaultChange'),
     onHasStoriesDisabledChanged: action('onHasStoriesDisabledChanged'),

ts/components/Preferences.tsx

@@ -96,6 +96,7 @@ export type PropsDataType = {
   hasAutoLaunch: boolean;
   hasCallNotifications: boolean;
   hasCallRingtoneNotification: boolean;
+  hasContentProtection: boolean;
   hasCountMutedConversations: boolean;
   hasHideMenuBar?: boolean;
   hasIncomingCallNotifications: boolean;
@@ -145,6 +146,8 @@ export type PropsDataType = {
   isSystemTraySupported: boolean;
   isMinimizeToAndStartInSystemTraySupported: boolean;
   isInternalUser: boolean;
+  isContentProtectionNeeded: boolean;
+  isContentProtectionSupported: boolean;
 
   availableCameras: Array<
     Pick<MediaDeviceInfo, 'deviceId' | 'groupId' | 'kind' | 'label'>
@@ -189,6 +192,7 @@ type PropsFunctionType = {
   onAutoLaunchChange: CheckboxChangeHandlerType;
   onCallNotificationsChange: CheckboxChangeHandlerType;
   onCallRingtoneNotificationChange: CheckboxChangeHandlerType;
+  onContentProtectionChange: CheckboxChangeHandlerType;
   onCountMutedConversationsChange: CheckboxChangeHandlerType;
   onEmojiSkinToneDefaultChange: (emojiSkinTone: EmojiSkinTone) => void;
   onHasStoriesDisabledChanged: SelectChangeHandlerType<boolean>;
@@ -297,6 +301,7 @@ export function Preferences({
   hasAutoLaunch,
   hasCallNotifications,
   hasCallRingtoneNotification,
+  hasContentProtection,
   hasCountMutedConversations,
   hasHideMenuBar,
   hasIncomingCallNotifications,
@@ -326,6 +331,8 @@ export function Preferences({
   isSystemTraySupported,
   isMinimizeToAndStartInSystemTraySupported,
   isInternalUser,
+  isContentProtectionNeeded,
+  isContentProtectionSupported,
   lastSyncTime,
   makeSyncRequest,
   notificationContent,
@@ -336,6 +343,7 @@ export function Preferences({
   onAutoLaunchChange,
   onCallNotificationsChange,
   onCallRingtoneNotificationChange,
+  onContentProtectionChange,
   onCountMutedConversationsChange,
   onEmojiSkinToneDefaultChange,
   onHasStoriesDisabledChanged,
@@ -392,6 +400,8 @@ export function Preferences({
 
   const [confirmDelete, setConfirmDelete] = useState(false);
   const [confirmStoriesOff, setConfirmStoriesOff] = useState(false);
+  const [confirmContentProtection, setConfirmContentProtection] =
+    useState(false);
   const [page, setPage] = useState<Page>(initialPage);
   const [showSyncFailed, setShowSyncFailed] = useState(false);
   const [nowSyncing, setNowSyncing] = useState(false);
@@ -460,6 +470,17 @@ export function Preferences({
     [onSelectedMicrophoneChange, availableMicrophones]
   );
 
+  const handleContentProtectionChange = useCallback(
+    (value: boolean) => {
+      if (value === true || !isContentProtectionNeeded) {
+        onContentProtectionChange(value);
+      } else {
+        setConfirmContentProtection(true);
+      }
+    },
+    [onContentProtectionChange, isContentProtectionNeeded]
+  );
+
   const settingsPaneRef = useRef<HTMLDivElement | null>(null);
   useEffect(() => {
     const settingsPane = settingsPaneRef.current;
@@ -1365,6 +1386,41 @@ export function Preferences({
             }
           />
         </SettingsRow>
+        {isContentProtectionSupported && (
+          <SettingsRow title={i18n('icu:Preferences__Privacy__Application')}>
+            <Checkbox
+              checked={hasContentProtection}
+              description={i18n(
+                'icu:Preferences__content-protection--description'
+              )}
+              label={i18n('icu:Preferences__content-protection--label')}
+              moduleClassName="Preferences__checkbox"
+              name="contentProtection"
+              onChange={handleContentProtectionChange}
+            />
+          </SettingsRow>
+        )}
+        {confirmContentProtection ? (
+          <ConfirmationDialog
+            dialogName="Preference.confirmContentProtection"
+            actions={[
+              {
+                action: () => onContentProtectionChange(false),
+                style: 'negative',
+                text: i18n(
+                  'icu:Preferences__content-protection__modal--disable'
+                ),
+              },
+            ]}
+            i18n={i18n}
+            onClose={() => {
+              setConfirmContentProtection(false);
+            }}
+            title={i18n('icu:Preferences__content-protection__modal--title')}
+          >
+            {i18n('icu:Preferences__content-protection__modal--body')}
+          </ConfirmationDialog>
+        ) : null}
         <SettingsRow title={i18n('icu:Stories__title')}>
           <Control
             left={

ts/main/settingsChannel.ts

@@ -21,6 +21,7 @@ const EPHEMERAL_NAME_MAP = new Map([
   ['systemTraySetting', 'system-tray-setting'],
   ['themeSetting', 'theme-setting'],
   ['localeOverride', 'localeOverride'],
+  ['contentProtection', 'contentProtection'],
 ]);
 
 type ResponseQueueEntry = Readonly<{
@@ -123,6 +124,7 @@ export class SettingsChannel extends EventEmitter {
     this.#installEphemeralSetting('systemTraySetting');
     this.#installEphemeralSetting('localeOverride');
     this.#installEphemeralSetting('spellCheck');
+    this.#installEphemeralSetting('contentProtection');
 
     installPermissionsHandler({ session: session.defaultSession, userConfig });
 
@@ -288,7 +290,7 @@ export class SettingsChannel extends EventEmitter {
       // Notify main to notify windows of preferences change. As for DB-backed
       // settings, those are set by the renderer, and afterwards the renderer IPC sends
       // to main the event 'preferences-changed'.
-      this.emit('ephemeral-setting-changed');
+      this.emit('ephemeral-setting-changed', name);
 
       const mainWindow = this.#mainWindow;
       if (!mainWindow || !mainWindow.webContents) {
@@ -308,7 +310,7 @@ export class SettingsChannel extends EventEmitter {
 
   public override on(
     type: 'ephemeral-setting-changed',
-    callback: () => void
+    callback: (name: string) => void
   ): this;
 
   public override on(
@@ -330,7 +332,10 @@ export class SettingsChannel extends EventEmitter {
     value: string
   ): boolean;
 
-  public override emit(type: 'ephemeral-setting-changed'): boolean;
+  public override emit(
+    type: 'ephemeral-setting-changed',
+    name: string
+  ): boolean;
 
   public override emit(
     type: SettingChangeEventType<keyof SettingsValuesType>,

ts/types/Settings.ts

@@ -33,6 +33,12 @@ export const isDrawAttentionSupported = (OS: OSType): boolean => !OS.isMacOS();
 export const isSystemTraySupported = (OS: OSType): boolean =>
   OS.isWindows() || OS.isLinux();
 
+export const isContentProtectionSupported = (OS: OSType): boolean =>
+  OS.isWindows() || OS.isMacOS();
+
+export const isContentProtectionNeeded = (OS: OSType): boolean =>
+  OS.isWindows();
+
 export const getDefaultSystemTraySetting = (
   OS: OSType,
   appVersion: string

ts/util/createIPCEvents.ts

@@ -192,6 +192,8 @@ type ValuesWithGetters = Omit<
   | 'mediaPermissions'
   | 'mediaCameraPermissions'
   | 'autoLaunch'
+  | 'spellCheck'
+  | 'contentProtection'
   | 'systemTraySetting'
 >;
 
@@ -240,6 +242,7 @@ export type IPCEventsGettersType = {
   getZoomFactor: () => Promise<ZoomFactorType>;
   getLocaleOverride: () => Promise<string | null>;
   getSpellCheck: () => Promise<boolean>;
+  getContentProtection: () => Promise<boolean>;
   getSystemTraySetting: () => Promise<SystemTraySetting>;
   getThemeSetting: () => Promise<ThemeType>;
   // Events
@@ -338,6 +341,12 @@ export function createIPCEvents(
       account.captureChange('hasStoriesDisabled');
       window.textsecure.server?.onHasStoriesDisabledChange(value);
     },
+    getContentProtection: () => {
+      return getEphemeralSetting('contentProtection');
+    },
+    setContentProtection: async (value: boolean) => {
+      await setEphemeralSetting('contentProtection', value);
+    },
     getStoryViewReceiptsEnabled: () => {
       return (
         window.storage.get('storyViewReceiptsEnabled') ??

ts/util/preload.ts

@@ -26,6 +26,7 @@ export type ThemeType = 'light' | 'dark' | 'system';
 
 export type EphemeralSettings = {
   spellCheck: boolean;
+  contentProtection: boolean;
   systemTraySetting: SystemTraySetting;
   themeSetting: ThemeType;
   localeOverride: string | null;

ts/windows/settings/app.tsx

@@ -51,6 +51,7 @@ SettingsWindowProps.onRender(
     hasAutoLaunch,
     hasCallNotifications,
     hasCallRingtoneNotification,
+    hasContentProtection,
     hasCountMutedConversations,
     hasHideMenuBar,
     hasIncomingCallNotifications,
@@ -77,6 +78,8 @@ SettingsWindowProps.onRender(
     isNotificationAttentionSupported,
     isSyncSupported,
     isSystemTraySupported,
+    isContentProtectionSupported,
+    isContentProtectionNeeded,
     isInternalUser,
     lastSyncTime,
     makeSyncRequest,
@@ -88,6 +91,7 @@ SettingsWindowProps.onRender(
     onAutoLaunchChange,
     onCallNotificationsChange,
     onCallRingtoneNotificationChange,
+    onContentProtectionChange,
     onCountMutedConversationsChange,
     onEmojiSkinToneDefaultChange,
     onHasStoriesDisabledChanged,
@@ -166,6 +170,7 @@ SettingsWindowProps.onRender(
           hasAutoLaunch={hasAutoLaunch}
           hasCallNotifications={hasCallNotifications}
           hasCallRingtoneNotification={hasCallRingtoneNotification}
+          hasContentProtection={hasContentProtection}
           hasCountMutedConversations={hasCountMutedConversations}
           hasHideMenuBar={hasHideMenuBar}
           hasIncomingCallNotifications={hasIncomingCallNotifications}
@@ -195,6 +200,8 @@ SettingsWindowProps.onRender(
           isNotificationAttentionSupported={isNotificationAttentionSupported}
           isSyncSupported={isSyncSupported}
           isSystemTraySupported={isSystemTraySupported}
+          isContentProtectionSupported={isContentProtectionSupported}
+          isContentProtectionNeeded={isContentProtectionNeeded}
           isInternalUser={isInternalUser}
           lastSyncTime={lastSyncTime}
           localeOverride={localeOverride}
@@ -207,6 +214,7 @@ SettingsWindowProps.onRender(
           onAutoLaunchChange={onAutoLaunchChange}
           onCallNotificationsChange={onCallNotificationsChange}
           onCallRingtoneNotificationChange={onCallRingtoneNotificationChange}
+          onContentProtectionChange={onContentProtectionChange}
           onCountMutedConversationsChange={onCountMutedConversationsChange}
           onEmojiSkinToneDefaultChange={onEmojiSkinToneDefaultChange}
           onHasStoriesDisabledChanged={onHasStoriesDisabledChanged}

ts/windows/settings/preload.ts

@@ -48,6 +48,7 @@ const settingNotificationSetting = createSetting('notificationSetting');
 const settingRelayCalls = createSetting('alwaysRelayCalls');
 const settingSentMediaQuality = createSetting('sentMediaQualitySetting');
 const settingSpellCheck = createSetting('spellCheck');
+const settingContentProtection = createSetting('contentProtection');
 const settingTextFormatting = createSetting('textFormatting');
 const settingTheme = createSetting('themeSetting');
 const settingSystemTraySetting = createSetting('systemTraySetting');
@@ -176,6 +177,7 @@ async function renderPreferences() {
     hasAutoLaunch,
     hasCallNotifications,
     hasCallRingtoneNotification,
+    hasContentProtection,
     hasCountMutedConversations,
     hasHideMenuBar,
     hasIncomingCallNotifications,
@@ -223,6 +225,7 @@ async function renderPreferences() {
     hasAutoLaunch: settingAutoLaunch.getValue(),
     hasCallNotifications: settingCallSystemNotification.getValue(),
     hasCallRingtoneNotification: settingCallRingtoneNotification.getValue(),
+    hasContentProtection: settingContentProtection.getValue(),
     hasCountMutedConversations: settingCountMutedConversations.getValue(),
     hasHideMenuBar: settingHideMenuBar.getValue(),
     hasIncomingCallNotifications: settingIncomingCallNotification.getValue(),
@@ -321,6 +324,7 @@ async function renderPreferences() {
     hasAutoLaunch,
     hasCallNotifications,
     hasCallRingtoneNotification,
+    hasContentProtection,
     hasCountMutedConversations,
     hasHideMenuBar,
     hasIncomingCallNotifications,
@@ -385,6 +389,8 @@ async function renderPreferences() {
     isSyncSupported: !isSyncNotSupported,
     isInternalUser,
     isSystemTraySupported: Settings.isSystemTraySupported(OS),
+    isContentProtectionSupported: Settings.isContentProtectionSupported(OS),
+    isContentProtectionNeeded: Settings.isContentProtectionNeeded(OS),
     isMinimizeToAndStartInSystemTraySupported:
       Settings.isMinimizeToAndStartInSystemTraySupported(OS),
 
@@ -408,6 +414,9 @@ async function renderPreferences() {
     onCallRingtoneNotificationChange: attachRenderCallback(
       settingCallRingtoneNotification.setValue
     ),
+    onContentProtectionChange: attachRenderCallback(
+      settingContentProtection.setValue
+    ),
     onCountMutedConversationsChange: attachRenderCallback(
       settingCountMutedConversations.setValue
     ),