Show critical-idle-primary-device banner in response to WS upgrade response headers

_locales/en/messages.json

@@ -6675,6 +6675,14 @@
     "messageformat": "Update Downloaded",
     "description": "The title of update dialog when update download is completed."
   },
+  "icu:CriticalIdlePrimaryDevice__title": {
+    "messageformat": "Open Signal on your phone",
+    "description": "Title of a banner alerting users if their primary device (e.g. phone) has not been logged into recently."
+  },
+  "icu:CriticalIdlePrimaryDevice__body": {
+    "messageformat": "Your account will be deleted soon unless you open Signal on your phone. This message will go away if you've done it successfully. <learnMoreLink>Learn more</learnMoreLink>",
+    "description": "The text in a banner alerting users if their primary device (e.g. phone) has not been logged into recently. "
+  },
   "icu:DialogNetworkStatus__outage": {
     "messageformat": "Signal is experiencing technical difficulties. We are working hard to restore service as quickly as possible.",
     "description": "The title of outage dialog during service outage."

package.json

@@ -221,7 +221,7 @@
     "@indutny/parallel-prettier": "3.0.0",
     "@indutny/rezip-electron": "2.0.1",
     "@napi-rs/canvas": "0.1.61",
-    "@signalapp/mock-server": "11.0.0",
+    "@signalapp/mock-server": "11.1.0",
     "@storybook/addon-a11y": "8.4.4",
     "@storybook/addon-actions": "8.4.4",
     "@storybook/addon-controls": "8.4.4",
@@ -374,6 +374,7 @@
       "app-builder-lib@26.0.0-alpha.8": "patches/app-builder-lib+26.0.0-alpha.8.patch",
       "growing-file@0.1.3": "patches/growing-file+0.1.3.patch",
       "websocket@1.0.34": "patches/websocket+1.0.34.patch",
+      "@types/websocket@1.0.0": "patches/@types+websocket+1.0.0.patch",
       "backbone@1.6.0": "patches/backbone+1.6.0.patch",
       "node-fetch@2.6.7": "patches/node-fetch+2.6.7.patch",
       "zod@3.23.8": "patches/zod+3.23.8.patch"

patches/@types+websocket+1.0.0.patch

@@ -0,0 +1,16 @@
+diff --git a/index.d.ts b/index.d.ts
+index eb23f3c479e6d368e1563de7531a8459566d5c56..146769d33ce61f036371c05743cd31fb44d25d49 100644
+--- a/index.d.ts
++++ b/index.d.ts
+@@ -650,9 +650,11 @@ export class client extends events.EventEmitter {
+     on(event: 'connect', cb: (connection: connection) => void): this;
+     on(event: 'connectFailed', cb: (err: Error) => void): this;
+     on(event: 'httpResponse', cb: (response: http.IncomingMessage, client: client) => void): this;
++    on(event: 'upgradeResponse', cb: (response: http.IncomingMessage) => void): this;
+     addListener(event: 'connect', cb: (connection: connection) => void): this;
+     addListener(event: 'connectFailed', cb: (err: Error) => void): this;
+     addListener(event: 'httpResponse', cb: (response: http.IncomingMessage, client: client) => void): this;
++    addListener(event: 'upgradeResponse', cb: (response: http.IncomingMessage) => void): this;
+ }
+ 
+ export interface IRouterRequest extends events.EventEmitter {

patches/websocket+1.0.34.patch

@@ -1,5 +1,17 @@
+diff --git a/lib/WebSocketClient.js b/lib/WebSocketClient.js
+index fb7572b382de289f7fa3ff35a9647f118f3bd4eb..0000a94607520b4b7ac71f5eee4ed297df8d1bf7 100644
+--- a/lib/WebSocketClient.js
++++ b/lib/WebSocketClient.js
+@@ -258,6 +258,7 @@ WebSocketClient.prototype.connect = function(requestUrl, protocols, origin, head
+         self.socket = socket;
+         self.response = response;
+         self.firstDataChunk = head;
++        self.emit('upgradeResponse', response);
+         self.validateHandshake();
+     });
+     req.on('error', handleRequestError);
 diff --git a/lib/WebSocketConnection.js b/lib/WebSocketConnection.js
-index 219de63..93d3800 100644
+index 219de631dabe578e64574732fc95353a1c1047fa..93d380004b5bc58ba9895fb5a760709389641071 100644
 --- a/lib/WebSocketConnection.js
 +++ b/lib/WebSocketConnection.js
 @@ -271,7 +271,7 @@ WebSocketConnection.prototype.handleSocketData = function(data) {

pnpm-lock.yaml

@@ -26,6 +26,9 @@ patchedDependencies:
   '@types/node-fetch@2.6.12':
     hash: bc43fb8cfed85fb4f7917b5bd3b47644ae15a000c26a6fe23078b2f5217efaf0
     path: patches/@types+node-fetch+2.6.12.patch
+  '@types/websocket@1.0.0':
+    hash: 53fdd65a6b35f379eb8f5807d315f00c66e9bfe9741f4859a0fa21026bdb30fa
+    path: patches/@types+websocket+1.0.0.patch
   '@vitest/expect@2.0.5':
     hash: e8a96f71e52bf903c9f1eadba4740489a0beb48da33db52354adca484fe1f495
     path: patches/@vitest+expect+2.0.5.patch
@@ -72,7 +75,7 @@ patchedDependencies:
     hash: 94614db18e4db7ff5eee4c2acf88e3ef245bff2f9637416e99e401bec3531286
     path: patches/react-textarea-autosize+8.5.5.patch
   websocket@1.0.34:
-    hash: 4ce5bb237501a5576bd9e09fbff46551dd3e57f7702f6033bcffa49dde7f71bb
+    hash: b8d361a6a73e44000bb51102dea0d841c22d2bb455dd6c54de566d0e0bd86355
     path: patches/websocket+1.0.34.patch
   zod@3.23.8:
     hash: 239818e5d88990616205c8cdc1de1660bf5e18b157d00c4a5f726dde6094af4d
@@ -375,7 +378,7 @@ importers:
         version: 11.0.2
       websocket:
         specifier: 1.0.34
-        version: 1.0.34(patch_hash=4ce5bb237501a5576bd9e09fbff46551dd3e57f7702f6033bcffa49dde7f71bb)
+        version: 1.0.34(patch_hash=b8d361a6a73e44000bb51102dea0d841c22d2bb455dd6c54de566d0e0bd86355)
       write-file-atomic:
         specifier: 6.0.0
         version: 6.0.0
@@ -429,8 +432,8 @@ importers:
         specifier: 0.1.61
         version: 0.1.61
       '@signalapp/mock-server':
-        specifier: 11.0.0
+        specifier: 11.1.0
-        version: 11.0.0(bufferutil@4.0.9)(utf-8-validate@5.0.10)
+        version: 11.1.0(bufferutil@4.0.9)(utf-8-validate@5.0.10)
       '@storybook/addon-a11y':
         specifier: 8.4.4
         version: 8.4.4(storybook@8.4.4(bufferutil@4.0.9)(prettier@3.3.3)(utf-8-validate@5.0.10))
@@ -586,7 +589,7 @@ importers:
         version: 10.0.0
       '@types/websocket':
         specifier: 1.0.0
-        version: 1.0.0
+        version: 1.0.0(patch_hash=53fdd65a6b35f379eb8f5807d315f00c66e9bfe9741f4859a0fa21026bdb30fa)
       '@types/write-file-atomic':
         specifier: 4.0.3
         version: 4.0.3
@@ -2535,8 +2538,8 @@ packages:
   '@signalapp/libsignal-client@0.67.3':
     resolution: {integrity: sha512-GIiXJMqiIByPZbomytoYQcQLJ3pNgHBCjt5BvlE/3rkrmNwyXW1UVqszX6/WfZi91aqUapO4+7Op+8JCbDGRWA==}
 
-  '@signalapp/mock-server@11.0.0':
+  '@signalapp/mock-server@11.1.0':
-    resolution: {integrity: sha512-JHEqdjXvWcXyLJ90OtaTIQVtizH/w+rmnPplNmHuUiDZIQIEvE3lRyZFyIvgVTNg29lQWs/Gw/o+hICerdOChQ==}
+    resolution: {integrity: sha512-SYYek3QCh57vZZGNVQW+fSXMr+xHjnO8sMAFfj8DovjqW4HIBWbt3itGyyjxSoIXnaCMK346O6I/R79w8xY/aw==}
 
   '@signalapp/parchment-cjs@3.0.1':
     resolution: {integrity: sha512-hSBMQ1M7wE4GcC8ZeNtvpJF+DAJg3eIRRf1SiHS3I3Algav/sgJJNm6HIYm6muHuK7IJmuEjkL3ILSXgmu0RfQ==}
@@ -12266,7 +12269,7 @@ snapshots:
       type-fest: 4.26.1
       uuid: 8.3.2
 
-  '@signalapp/mock-server@11.0.0(bufferutil@4.0.9)(utf-8-validate@5.0.10)':
+  '@signalapp/mock-server@11.1.0(bufferutil@4.0.9)(utf-8-validate@5.0.10)':
     dependencies:
       '@indutny/parallel-prettier': 3.0.0(prettier@3.3.3)
       '@signalapp/libsignal-client': 0.60.2
@@ -13134,7 +13137,7 @@ snapshots:
     dependencies:
       '@types/node': 20.17.6
 
-  '@types/websocket@1.0.0':
+  '@types/websocket@1.0.0(patch_hash=53fdd65a6b35f379eb8f5807d315f00c66e9bfe9741f4859a0fa21026bdb30fa)':
     dependencies:
       '@types/node': 20.17.6
 
@@ -20849,7 +20852,7 @@ snapshots:
 
   websocket-extensions@0.1.4: {}
 
-  websocket@1.0.34(patch_hash=4ce5bb237501a5576bd9e09fbff46551dd3e57f7702f6033bcffa49dde7f71bb):
+  websocket@1.0.34(patch_hash=b8d361a6a73e44000bb51102dea0d841c22d2bb455dd6c54de566d0e0bd86355):
     dependencies:
       bufferutil: 4.0.9
       debug: 2.6.9

ts/background.ts

@@ -208,6 +208,7 @@ import { handleDataMessage } from './messages/handleDataMessage';
 import { MessageModel } from './models/messages';
 import { waitForEvent } from './shims/events';
 import { sendSyncRequests } from './textsecure/syncRequests';
+import { handleServerAlerts } from './util/handleServerAlerts';
 
 export function isOverHourIntoPast(timestamp: number): boolean {
   return isNumber(timestamp) && isOlderThan(timestamp, HOUR);
@@ -511,6 +512,8 @@ export async function startApp(): Promise<void> {
     restoreRemoteConfigFromStorage();
 
     window.Whisper.events.on('firstEnvelope', checkFirstEnvelope);
+    window.Whisper.events.on('serverAlerts', handleServerAlerts);
+
     server = window.WebAPI.connect({
       ...window.textsecure.storage.user.getWebAPICredentials(),
       hasStoriesDisabled: window.storage.get('hasStoriesDisabled', false),

ts/components/CriticalIdlePrimaryDeviceDialog.tsx

@@ -0,0 +1,46 @@
+// Copyright 2025 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import React from 'react';
+
+import { LeftPaneDialog } from './LeftPaneDialog';
+import type { WidthBreakpoint } from './_util';
+import type { LocalizerType } from '../types/I18N';
+import { I18n } from './I18n';
+
+export type PropsType = {
+  containerWidthBreakpoint: WidthBreakpoint;
+  i18n: LocalizerType;
+};
+
+export function CriticalIdlePrimaryDeviceDialog({
+  containerWidthBreakpoint,
+  i18n,
+}: PropsType): JSX.Element {
+  const learnMoreLink = (parts: Array<string | JSX.Element>) => (
+    <a
+      key="signal-support"
+      // TODO: DESKTOP-8377
+      href="https://support.signal.org/"
+      rel="noreferrer"
+      target="_blank"
+    >
+      {parts}
+    </a>
+  );
+  return (
+    <LeftPaneDialog
+      containerWidthBreakpoint={containerWidthBreakpoint}
+      type="warning"
+      title={i18n('icu:CriticalIdlePrimaryDevice__title')}
+    >
+      <I18n
+        id="icu:CriticalIdlePrimaryDevice__body"
+        i18n={i18n}
+        components={{
+          learnMoreLink,
+        }}
+      />
+    </LeftPaneDialog>
+  );
+}

ts/components/LeftPane.stories.tsx

@@ -35,6 +35,7 @@ import {
   useUuidFetchState,
 } from '../test-both/helpers/fakeLookupConversationWithoutServiceId';
 import type { GroupListItemConversationType } from './conversationList/GroupListItem';
+import { CriticalIdlePrimaryDeviceDialog } from './CriticalIdlePrimaryDeviceDialog';
 
 const i18n = setupI18n('en', enMessages);
 
@@ -173,6 +174,7 @@ const useProps = (overrideProps: OverridePropsType = {}): PropsType => {
     getPreferredBadge: () => undefined,
     hasFailedStorySends: false,
     hasPendingUpdate: false,
+    hasCriticalIdlePrimaryDeviceAlert: false,
     i18n,
     isMacOS: false,
     preferredWidthFromStorage: 320,
@@ -271,6 +273,9 @@ const useProps = (overrideProps: OverridePropsType = {}): PropsType => {
       />
     ),
     renderExpiredBuildDialog: props => <DialogExpiredBuild {...props} />,
+    renderCriticalIdlePrimaryDeviceDialog: props => (
+      <CriticalIdlePrimaryDeviceDialog {...props} />
+    ),
     renderUnsupportedOSDialog: props => (
       <UnsupportedOSDialog
         i18n={i18n}
@@ -393,6 +398,15 @@ export function InboxBackupMediaDownloadWithDialogsAndUnpinnedConversations(): J
     />
   );
 }
+export function InboxCriticalIdlePrimaryDeviceAlert(): JSX.Element {
+  return (
+    <LeftPaneInContainer
+      {...useProps({
+        hasCriticalIdlePrimaryDeviceAlert: true,
+      })}
+    />
+  );
+}
 
 export function InboxUsernameCorrupted(): JSX.Element {
   return (

ts/components/LeftPane.tsx

@@ -69,6 +69,7 @@ export type PropsType = {
   otherTabsUnreadStats: UnreadStats;
   hasExpiredDialog: boolean;
   hasFailedStorySends: boolean;
+  hasCriticalIdlePrimaryDeviceAlert: boolean;
   hasNetworkDialog: boolean;
   hasPendingUpdate: boolean;
   hasRelinkDialog: boolean;
@@ -180,6 +181,12 @@ export type PropsType = {
   renderCaptchaDialog: (props: { onSkip(): void }) => JSX.Element;
   renderCrashReportDialog: () => JSX.Element;
   renderExpiredBuildDialog: (_: DialogExpiredBuildPropsType) => JSX.Element;
+  renderCriticalIdlePrimaryDeviceDialog: (
+    _: Readonly<{
+      containerWidthBreakpoint: WidthBreakpoint;
+      i18n: LocalizerType;
+    }>
+  ) => JSX.Element;
   renderToastManager: (_: {
     containerWidthBreakpoint: WidthBreakpoint;
   }) => JSX.Element;
@@ -206,6 +213,7 @@ export function LeftPane({
   getPreferredBadge,
   hasExpiredDialog,
   hasFailedStorySends,
+  hasCriticalIdlePrimaryDeviceAlert,
   hasNetworkDialog,
   hasPendingUpdate,
   hasRelinkDialog,
@@ -227,6 +235,7 @@ export function LeftPane({
   renderCaptchaDialog,
   renderCrashReportDialog,
   renderExpiredBuildDialog,
+  renderCriticalIdlePrimaryDeviceDialog,
   renderMessageSearchResult,
   renderNetworkStatus,
   renderUnsupportedOSDialog,
@@ -611,6 +620,9 @@ export function LeftPane({
     maybeYellowDialog = renderNetworkStatus(commonDialogProps);
   } else if (hasRelinkDialog) {
     maybeYellowDialog = renderRelinkDialog(commonDialogProps);
+  } else if (hasCriticalIdlePrimaryDeviceAlert) {
+    maybeYellowDialog =
+      renderCriticalIdlePrimaryDeviceDialog(commonDialogProps);
   }
 
   // Update dialog

ts/state/actions.ts

@@ -23,6 +23,7 @@ import { actions as mediaGallery } from './ducks/mediaGallery';
 import { actions as network } from './ducks/network';
 import { actions as safetyNumber } from './ducks/safetyNumber';
 import { actions as search } from './ducks/search';
+import { actions as server } from './ducks/server';
 import { actions as stickers } from './ducks/stickers';
 import { actions as stories } from './ducks/stories';
 import { actions as storyDistributionLists } from './ducks/storyDistributionLists';
@@ -55,6 +56,7 @@ export const actionCreators: ReduxActions = {
   network,
   safetyNumber,
   search,
+  server,
   stickers,
   stories,
   storyDistributionLists,

ts/state/ducks/server.ts

@@ -0,0 +1,59 @@
+// Copyright 2020 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { ReadonlyDeep } from 'type-fest';
+
+// State
+
+export enum ServerAlert {
+  CRITICAL_IDLE_PRIMARY_DEVICE = 'critical_idle_primary_device',
+}
+
+export type ServerStateType = ReadonlyDeep<{
+  alerts: Array<ServerAlert>;
+}>;
+
+// Actions
+
+const UPDATE_SERVER_ALERTS = 'server/UPDATE_SERVER_ALERTS';
+
+type UpdateServerAlertsType = ReadonlyDeep<{
+  type: 'server/UPDATE_SERVER_ALERTS';
+  payload: { alerts: Array<ServerAlert> };
+}>;
+
+export type ServerActionType = ReadonlyDeep<UpdateServerAlertsType>;
+
+// Action Creators
+
+function updateServerAlerts(alerts: Array<ServerAlert>): ServerActionType {
+  return {
+    type: UPDATE_SERVER_ALERTS,
+    payload: { alerts },
+  };
+}
+
+export const actions = {
+  updateServerAlerts,
+};
+
+// Reducer
+
+export function getEmptyState(): ServerStateType {
+  return {
+    alerts: [],
+  };
+}
+
+export function reducer(
+  state: Readonly<ServerStateType> = getEmptyState(),
+  action: Readonly<ServerActionType>
+): ServerStateType {
+  if (action.type === UPDATE_SERVER_ALERTS) {
+    return {
+      alerts: action.payload.alerts,
+    };
+  }
+
+  return state;
+}

ts/state/getInitialState.ts

@@ -25,6 +25,7 @@ import { getEmptyState as networkEmptyState } from './ducks/network';
 import { getEmptyState as preferredReactionsEmptyState } from './ducks/preferredReactions';
 import { getEmptyState as safetyNumberEmptyState } from './ducks/safetyNumber';
 import { getEmptyState as searchEmptyState } from './ducks/search';
+import { getEmptyState as serverEmptyState } from './ducks/server';
 import { getEmptyState as stickersEmptyState } from './ducks/stickers';
 import { getEmptyState as storiesEmptyState } from './ducks/stories';
 import { getEmptyState as storyDistributionListsEmptyState } from './ducks/storyDistributionLists';
@@ -144,6 +145,7 @@ function getEmptyState(): StateType {
     preferredReactions: preferredReactionsEmptyState(),
     safetyNumber: safetyNumberEmptyState(),
     search: searchEmptyState(),
+    server: serverEmptyState(),
     stickers: stickersEmptyState(),
     stories: storiesEmptyState(),
     storyDistributionLists: storyDistributionListsEmptyState(),

ts/state/initializeRedux.ts

@@ -83,6 +83,7 @@ export function initializeRedux(data: ReduxInitData): void {
       store.dispatch
     ),
     search: bindActionCreators(actionCreators.search, store.dispatch),
+    server: bindActionCreators(actionCreators.server, store.dispatch),
     stickers: bindActionCreators(actionCreators.stickers, store.dispatch),
     stories: bindActionCreators(actionCreators.stories, store.dispatch),
     storyDistributionLists: bindActionCreators(

ts/state/reducer.ts

@@ -27,6 +27,7 @@ import { reducer as network } from './ducks/network';
 import { reducer as preferredReactions } from './ducks/preferredReactions';
 import { reducer as safetyNumber } from './ducks/safetyNumber';
 import { reducer as search } from './ducks/search';
+import { reducer as server } from './ducks/server';
 import { reducer as stickers } from './ducks/stickers';
 import { reducer as stories } from './ducks/stories';
 import { reducer as storyDistributionLists } from './ducks/storyDistributionLists';
@@ -60,6 +61,7 @@ export const reducer = combineReducers({
   preferredReactions,
   safetyNumber,
   search,
+  server,
   stickers,
   stories,
   storyDistributionLists,

ts/state/selectors/server.ts

@@ -0,0 +1,17 @@
+// Copyright 2025 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { createSelector } from 'reselect';
+
+import type { StateType } from '../reducer';
+import { ServerAlert } from '../ducks/server';
+
+export const getServerAlerts = (state: StateType): ReadonlyArray<ServerAlert> =>
+  state.server.alerts;
+
+export const getHasCriticalIdlePrimaryDeviceAlert = createSelector(
+  getServerAlerts,
+  (alerts): boolean => {
+    return alerts.includes(ServerAlert.CRITICAL_IDLE_PRIMARY_DEVICE);
+  }
+);

ts/state/smart/LeftPane.tsx

@@ -104,6 +104,9 @@ import {
   pauseBackupMediaDownload,
   resumeBackupMediaDownload,
 } from '../../util/backupMediaDownload';
+import { getHasCriticalIdlePrimaryDeviceAlert } from '../selectors/server';
+import { CriticalIdlePrimaryDeviceDialog } from '../../components/CriticalIdlePrimaryDeviceDialog';
+import type { LocalizerType } from '../../types/I18N';
 
 function renderMessageSearchResult(id: string): JSX.Element {
   return <SmartMessageSearchResult id={id} />;
@@ -123,7 +126,14 @@ function renderUpdateDialog(
 ): JSX.Element {
   return <SmartUpdateDialog {...props} />;
 }
-
+function renderCriticalIdlePrimaryDeviceDialog(
+  props: Readonly<{
+    containerWidthBreakpoint: WidthBreakpoint;
+    i18n: LocalizerType;
+  }>
+): JSX.Element {
+  return <CriticalIdlePrimaryDeviceDialog {...props} />;
+}
 function renderCaptchaDialog({ onSkip }: { onSkip(): void }): JSX.Element {
   return <SmartCaptchaDialog onSkip={onSkip} />;
 }
@@ -297,6 +307,10 @@ export const SmartLeftPane = memo(function SmartLeftPane({
   const backupMediaDownloadProgress = useSelector(
     getBackupMediaDownloadProgress
   );
+  const hasCriticalIdlePrimaryDeviceAlert = useSelector(
+    getHasCriticalIdlePrimaryDeviceAlert
+  );
+
   const {
     blockConversation,
     clearGroupCreationError,
@@ -388,6 +402,7 @@ export const SmartLeftPane = memo(function SmartLeftPane({
       getPreferredBadge={getPreferredBadge}
       hasExpiredDialog={hasExpiredDialog}
       hasFailedStorySends={hasFailedStorySends}
+      hasCriticalIdlePrimaryDeviceAlert={hasCriticalIdlePrimaryDeviceAlert}
       hasNetworkDialog={hasNetworkDialog}
       hasPendingUpdate={hasPendingUpdate}
       hasRelinkDialog={hasRelinkDialog}
@@ -409,6 +424,9 @@ export const SmartLeftPane = memo(function SmartLeftPane({
       renderCaptchaDialog={renderCaptchaDialog}
       renderCrashReportDialog={renderCrashReportDialog}
       renderExpiredBuildDialog={renderExpiredBuildDialog}
+      renderCriticalIdlePrimaryDeviceDialog={
+        renderCriticalIdlePrimaryDeviceDialog
+      }
       renderMessageSearchResult={renderMessageSearchResult}
       renderNetworkStatus={renderNetworkStatus}
       renderRelinkDialog={renderRelinkDialog}

ts/state/types.ts

@@ -23,6 +23,7 @@ import type { actions as mediaGallery } from './ducks/mediaGallery';
 import type { actions as network } from './ducks/network';
 import type { actions as safetyNumber } from './ducks/safetyNumber';
 import type { actions as search } from './ducks/search';
+import type { actions as server } from './ducks/server';
 import type { actions as stickers } from './ducks/stickers';
 import type { actions as stories } from './ducks/stories';
 import type { actions as storyDistributionLists } from './ducks/storyDistributionLists';
@@ -54,6 +55,7 @@ export type ReduxActions = {
   network: typeof network;
   safetyNumber: typeof safetyNumber;
   search: typeof search;
+  server: typeof server;
   stickers: typeof stickers;
   stories: typeof stories;
   storyDistributionLists: typeof storyDistributionLists;

ts/test-mock/helpers.ts

@@ -252,12 +252,15 @@ export async function createGroup(
   await phone.setStorageState(state);
   return group;
 }
+export function getLeftPane(page: Page): Locator {
+  return page.locator('#LeftPane');
+}
 
 export async function clickOnConversationWithAci(
   page: Page,
   aci: string
 ): Promise<void> {
-  const leftPane = page.locator('#LeftPane');
+  const leftPane = getLeftPane(page);
   await leftPane.getByTestId(aci).click();
 }
 

ts/test-mock/network/serverAlerts_test.ts

@@ -0,0 +1,40 @@
+// Copyright 2025 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+import createDebug from 'debug';
+
+import type { App } from '../playwright';
+import { Bootstrap } from '../bootstrap';
+import { getLeftPane } from '../helpers';
+import { MINUTE } from '../../util/durations';
+
+export const debug = createDebug('mock:test:serverAlerts');
+
+describe('serverAlerts', function (this: Mocha.Suite) {
+  this.timeout(MINUTE);
+  let bootstrap: Bootstrap;
+  let app: App;
+
+  beforeEach(async () => {
+    bootstrap = new Bootstrap();
+    await bootstrap.init();
+  });
+
+  afterEach(async function (this: Mocha.Context) {
+    if (!bootstrap) {
+      return;
+    }
+
+    await bootstrap.maybeSaveLogs(this.currentTest, app);
+    await app.close();
+    await bootstrap.teardown();
+  });
+
+  it('shows idle primary device alert', async () => {
+    bootstrap.server.setWebsocketUpgradeResponseHeaders({
+      'X-Signal-Alert': 'critical-idle-primary-device',
+    });
+    app = await bootstrap.link();
+    const window = await app.getWindow();
+    await getLeftPane(window).getByText('Open Signal on your phone').waitFor();
+  });
+});

ts/textsecure/SocketManager.ts

@@ -12,6 +12,7 @@ import { Headers } from 'node-fetch';
 import type { connection as WebSocket } from 'websocket';
 import qs from 'querystring';
 import EventListener from 'events';
+import type { IncomingMessage } from 'http';
 
 import type { AbortableProcess } from '../util/AbortableProcess';
 import { strictAssert } from '../util/assert';
@@ -50,6 +51,7 @@ import { isNightly, isBeta, isStaging } from '../util/version';
 import { getBasicAuth } from '../util/getBasicAuth';
 import { isTestOrMockEnvironment } from '../environment';
 import type { ConfigKeyType } from '../RemoteConfig';
+import { ServerAlert } from '../state/ducks/server';
 
 const FIVE_MINUTES = 5 * durations.MINUTE;
 
@@ -220,6 +222,9 @@ export class SocketManager extends EventListener {
             Authorization: getBasicAuth({ username, password }),
             'X-Signal-Receive-Stories': String(!this.#hasStoriesDisabled),
           },
+          onUpgradeResponse: (response: IncomingMessage) => {
+            this.#handleAuthenticatedUpgradeResponseHeaders(response.headers);
+          },
           proxyAgent,
         });
 
@@ -758,6 +763,7 @@ export class SocketManager extends EventListener {
     resourceOptions,
     query = {},
     extraHeaders = {},
+    onUpgradeResponse,
     timeout,
   }: {
     name: string;
@@ -766,6 +772,7 @@ export class SocketManager extends EventListener {
     resourceOptions: WebSocketResourceOptions;
     query?: Record<string, string>;
     extraHeaders?: Record<string, string>;
+    onUpgradeResponse?: (response: IncomingMessage) => void;
     timeout?: number;
   }): AbortableProcess<IWebSocketResource> {
     const queryWithDefaults = {
@@ -787,6 +794,7 @@ export class SocketManager extends EventListener {
       timeout,
 
       extraHeaders,
+      onUpgradeResponse,
 
       createResource(socket: WebSocket): WebSocketResource {
         const duration = (performance.now() - start).toFixed(1);
@@ -947,6 +955,33 @@ export class SocketManager extends EventListener {
     return this.#lazyProxyAgent;
   }
 
+  #handleAuthenticatedUpgradeResponseHeaders(
+    headers: Record<string, string | Array<string> | undefined>
+  ) {
+    let alerts: Array<string> = [];
+    for (const [key, value] of Object.entries(headers)) {
+      if (key.toLowerCase() === 'x-signal-alert') {
+        if (value == null) {
+          alerts = [];
+        } else if (Array.isArray(value)) {
+          alerts = value;
+        } else {
+          alerts = [value];
+        }
+        break;
+      }
+    }
+
+    const serverAlerts: Array<ServerAlert> = [];
+    alerts.forEach(alert => {
+      if (alert.toLowerCase() === 'critical-idle-primary-device') {
+        serverAlerts.push(ServerAlert.CRITICAL_IDLE_PRIMARY_DEVICE);
+      }
+    });
+
+    this.emit('serverAlerts', serverAlerts);
+  }
+
   // EventEmitter types
 
   public override on(type: 'authError', callback: () => void): this;
@@ -957,6 +992,10 @@ export class SocketManager extends EventListener {
     type: 'firstEnvelope',
     callback: (incoming: IncomingWebSocketRequest) => void
   ): this;
+  public override on(
+    type: 'serverAlerts',
+    callback: (alerts: Array<ServerAlert>) => void
+  ): this;
 
   public override on(
     type: string | symbol,
@@ -974,6 +1013,10 @@ export class SocketManager extends EventListener {
     type: 'firstEnvelope',
     incoming: IncomingWebSocketRequest
   ): boolean;
+  public override emit(
+    type: 'serverAlerts',
+    alerts: Array<ServerAlert>
+  ): boolean;
 
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   public override emit(type: string | symbol, ...args: Array<any>): boolean {

ts/textsecure/WebAPI.ts

@@ -1812,6 +1812,10 @@ export function initialize({
       window.Whisper.events.trigger('firstEnvelope', incoming);
     });
 
+    socketManager.on('serverAlerts', alerts => {
+      window.Whisper.events.trigger('serverAlerts', alerts);
+    });
+
     if (useWebSocket) {
       void socketManager.authenticate({ username, password });
     }

ts/textsecure/WebSocket.ts

@@ -3,6 +3,7 @@
 
 import { client as WebSocketClient } from 'websocket';
 import type { connection as WebSocket } from 'websocket';
+import type { IncomingMessage } from 'http';
 
 import { AbortableProcess } from '../util/AbortableProcess';
 import { strictAssert } from '../util/assert';
@@ -32,6 +33,7 @@ export type ConnectOptionsType<Resource extends IResource> = Readonly<{
   proxyAgent?: ProxyAgent;
   timeout?: number;
   extraHeaders?: Record<string, string>;
+  onUpgradeResponse?: (response: IncomingMessage) => void;
 
   createResource(socket: WebSocket): Resource;
 }>;
@@ -44,6 +46,7 @@ export function connect<Resource extends IResource>({
   proxyAgent,
   extraHeaders = {},
   timeout = WEBSOCKET_CONNECT_TIMEOUT,
+  onUpgradeResponse,
   createResource,
 }: ConnectOptionsType<Resource>): AbortableProcess<Resource> {
   const fixedScheme = url
@@ -84,6 +87,10 @@ export function connect<Resource extends IResource>({
     resolve(resource);
   });
 
+  client.on('upgradeResponse', response => {
+    onUpgradeResponse?.(response);
+  });
+
   client.on('httpResponse', async response => {
     Timers.clearTimeout(timer);
 

ts/util/handleServerAlerts.ts

@@ -0,0 +1,8 @@
+// Copyright 2025 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { ServerAlert } from '../state/ducks/server';
+
+export function handleServerAlerts(alerts: Array<ServerAlert>): void {
+  window.reduxActions.server.updateServerAlerts(alerts);
+}