diff --git a/electron-builder.json b/electron-builder.json
index df4f28dd83..7891138eb0 100644
--- a/electron-builder.json
+++ b/electron-builder.json
@@ -18,7 +18,7 @@
     "category": "public.app-category.productivity",
     "target": ["dmg", "pkg", "zip", "mas"],
     "icon": "build/icon.icns",
-    "bundleVersion": "26107",
+    "bundleVersion": "26108",
     "helperBundleId": "chat.rocket.electron.helper",
     "type": "distribution",
     "artifactName": "rocketchat-${version}-${os}.${ext}",
diff --git a/package.json b/package.json
index fd93ecb8a4..e7aa0172d7 100644
--- a/package.json
+++ b/package.json
@@ -6,7 +6,7 @@
   "productName": "Rocket.Chat",
   "name": "rocketchat",
   "description": "Official OSX, Windows, and Linux Desktop Clients for Rocket.Chat",
-  "version": "4.18.1",
+  "version": "4.18.2",
   "author": "Rocket.Chat Support <support@rocket.chat>",
   "copyright": "© 2016-2026, Rocket.Chat",
   "homepage": "https://rocket.chat",
diff --git a/src/app/PersistableValues.ts b/src/app/PersistableValues.ts
index b66b4acb7a..99647cc215 100644
--- a/src/app/PersistableValues.ts
+++ b/src/app/PersistableValues.ts
@@ -160,6 +160,9 @@ export type PersistableValues = Omit<
 /** Current menu-bar default policy for Windows/Linux (auto-hide, Alt reveals). */
 export const MENU_BAR_DEFAULT_REVISION = 1;
 
+/** Mac App Store builds stored the internal video call window as off; turn it on once. */
+export const MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION = 1;
+
 export const migrations = {
   '>=3.1.0': (before: PersistableValues_0_0_0): PersistableValues_3_1_0 => {
     const { currentServerUrl, ...rest } = before;
@@ -189,7 +192,7 @@ export const migrations = {
   }),
   '>=3.8.4': (before: PersistableValues_3_8_1): PersistableValues_3_8_4 => ({
     ...before,
-    isInternalVideoChatWindowEnabled: !process.mas,
+    isInternalVideoChatWindowEnabled: true,
     isAddNewServersEnabled: true,
   }),
   '>=3.8.7': (before: PersistableValues_3_8_4): PersistableValues_3_8_7 => ({
diff --git a/src/app/__tests__/PersistableValues.spec.ts b/src/app/__tests__/PersistableValues.spec.ts
index a17b6003ff..1f6a0c97f9 100644
--- a/src/app/__tests__/PersistableValues.spec.ts
+++ b/src/app/__tests__/PersistableValues.spec.ts
@@ -235,7 +235,7 @@ describe('PersistableValues migrations', () => {
 
     setProcessMas(true);
     const mas384 = migrations['>=3.8.4'](win37 as any);
-    expect(mas384.isInternalVideoChatWindowEnabled).toBe(false);
+    expect(mas384.isInternalVideoChatWindowEnabled).toBe(true);
   });
 
   it('applies remaining migration defaults through 4.15.0', () => {
diff --git a/src/app/main/data.spec.ts b/src/app/main/data.spec.ts
index 360651d747..95a1e3f7ae 100644
--- a/src/app/main/data.spec.ts
+++ b/src/app/main/data.spec.ts
@@ -1,7 +1,10 @@
 import fs from 'fs';
 
 import * as store from '../../store';
-import { MENU_BAR_DEFAULT_REVISION } from '../PersistableValues';
+import {
+  MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION,
+  MENU_BAR_DEFAULT_REVISION,
+} from '../PersistableValues';
 import { APP_SETTINGS_LOADED } from '../actions';
 import { mergePersistableValues } from './data';
 import {
@@ -195,6 +198,117 @@ describe('mergePersistableValues', () => {
     });
   });
 
+  describe('Mac App Store internal video call window default', () => {
+    const processMasDescriptor = Object.getOwnPropertyDescriptor(
+      process,
+      'mas'
+    );
+
+    const mockMasRevision = (revision: number) => {
+      (getPersistedMeta as jest.Mock).mockImplementation(
+        (key: string, fallback: unknown) => {
+          if (key === 'masInternalVideoChatWindowDefaultRevision') {
+            return revision;
+          }
+          if (key === 'menuBarDefaultRevision') {
+            return MENU_BAR_DEFAULT_REVISION;
+          }
+          return fallback;
+        }
+      );
+    };
+
+    beforeEach(() => {
+      Object.defineProperty(process, 'mas', {
+        value: true,
+        writable: true,
+        configurable: true,
+      });
+      mockSelect.mockReturnValue({
+        ...mockInitialValues,
+        isInternalVideoChatWindowEnabled: false,
+      });
+    });
+
+    afterEach(() => {
+      if (processMasDescriptor) {
+        Object.defineProperty(process, 'mas', processMasDescriptor);
+      } else {
+        delete (process as { mas?: boolean }).mas;
+      }
+    });
+
+    it('one-shot: turns the internal window on when the revision is stale', async () => {
+      mockMasRevision(0);
+
+      await mergePersistableValues({});
+
+      expect(mockDispatch).toHaveBeenCalledWith({
+        type: APP_SETTINGS_LOADED,
+        payload: expect.objectContaining({
+          isInternalVideoChatWindowEnabled: true,
+        }),
+      });
+      expect(setPersistedMeta).toHaveBeenCalledWith(
+        'masInternalVideoChatWindowDefaultRevision',
+        MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION
+      );
+    });
+
+    it('one-shot: keeps the user choice after the revision is applied', async () => {
+      mockMasRevision(MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION);
+
+      await mergePersistableValues({});
+
+      expect(mockDispatch).toHaveBeenCalledWith({
+        type: APP_SETTINGS_LOADED,
+        payload: expect.objectContaining({
+          isInternalVideoChatWindowEnabled: false,
+        }),
+      });
+      expect(setPersistedMeta).not.toHaveBeenCalled();
+    });
+
+    it('one-shot: keeps an overridden-settings.json value', async () => {
+      mockMasRevision(0);
+      (fs.promises.readFile as jest.Mock).mockResolvedValueOnce(
+        JSON.stringify({ isInternalVideoChatWindowEnabled: false })
+      );
+
+      await mergePersistableValues({});
+
+      expect(mockDispatch).toHaveBeenCalledWith({
+        type: APP_SETTINGS_LOADED,
+        payload: expect.objectContaining({
+          isInternalVideoChatWindowEnabled: false,
+        }),
+      });
+      expect(setPersistedMeta).toHaveBeenCalledWith(
+        'masInternalVideoChatWindowDefaultRevision',
+        MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION
+      );
+    });
+
+    it('does nothing outside the Mac App Store build', async () => {
+      Object.defineProperty(process, 'mas', {
+        value: false,
+        writable: true,
+        configurable: true,
+      });
+      mockMasRevision(0);
+
+      await mergePersistableValues({});
+
+      expect(mockDispatch).toHaveBeenCalledWith({
+        type: APP_SETTINGS_LOADED,
+        payload: expect.objectContaining({
+          isInternalVideoChatWindowEnabled: false,
+        }),
+      });
+      expect(setPersistedMeta).not.toHaveBeenCalled();
+    });
+  });
+
   describe('legacy localStorage migration', () => {
     it('should handle autohideMenu from localStorage', async () => {
       const localStorage = {
diff --git a/src/app/main/data.ts b/src/app/main/data.ts
index 47090a15b0..ae330db28f 100644
--- a/src/app/main/data.ts
+++ b/src/app/main/data.ts
@@ -7,7 +7,10 @@ import { logger } from '../../logging';
 import { select, dispatch, watch } from '../../store';
 import { getSystemCertificateStatus } from '../../systemCertificates';
 import { normalizeNumber } from '../../ui/main/rootWindow';
-import { MENU_BAR_DEFAULT_REVISION } from '../PersistableValues';
+import {
+  MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION,
+  MENU_BAR_DEFAULT_REVISION,
+} from '../PersistableValues';
 import { APP_SETTINGS_LOADED } from '../actions';
 import { selectPersistableValues } from '../selectors';
 import {
@@ -178,6 +181,34 @@ export const mergePersistableValues = async (
     setPersistedMeta('menuBarDefaultRevision', MENU_BAR_DEFAULT_REVISION);
   }
 
+  // One-shot policy: Mac App Store builds used to force the internal video
+  // call window off. Turn it on once; a later user choice or an
+  // overridden-settings.json value still wins.
+  if (process.mas) {
+    const appliedMasVideoCallRevision = getPersistedMeta(
+      'masInternalVideoChatWindowDefaultRevision',
+      0
+    );
+    if (
+      appliedMasVideoCallRevision <
+      MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION
+    ) {
+      const isOverridden =
+        'isInternalVideoChatWindowEnabled' in userDataPersistableOverrides ||
+        'isInternalVideoChatWindowEnabled' in appAsarPersistableOverrides;
+      if (!isOverridden) {
+        values = {
+          ...values,
+          isInternalVideoChatWindowEnabled: true,
+        };
+      }
+      setPersistedMeta(
+        'masInternalVideoChatWindowDefaultRevision',
+        MAS_INTERNAL_VIDEO_CHAT_WINDOW_DEFAULT_REVISION
+      );
+    }
+  }
+
   const mergedOverrides: Record<string, unknown> = {
     ...userDataOverriddenSettings,
     ...appAsarOverriddenSettings,
diff --git a/src/i18n/de-DE.i18n.json b/src/i18n/de-DE.i18n.json
index f9ebc4a36a..f1ea552891 100644
--- a/src/i18n/de-DE.i18n.json
+++ b/src/i18n/de-DE.i18n.json
@@ -243,8 +243,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Öffnen Sie den Video-Chat mit dem Anwendungsfenster",
-        "description": "Wenn diese Option aktiviert ist, wird der Video-Chat im Anwendungsfenster anstelle des Standardbrowsers geöffnet. Allerdings wird für <strong>Google Meet</strong> und <strong>Jitsi</strong> die Bildschirmaufzeichnung in Electron-Anwendungen nicht unterstützt, daher werden sie unabhängig von dieser Einstellung immer im Browser geöffnet.",
-        "masDescription": "Diese Option ist deaktiviert, wenn sie aus dem Mac App Store installiert wird. Aus Sicherheitsgründen wird der Video-Chat standardmäßig über den Browser geöffnet."
+        "description": "Wenn diese Option aktiviert ist, wird der Video-Chat im Anwendungsfenster anstelle des Standardbrowsers geöffnet. Allerdings wird für <strong>Google Meet</strong> die Bildschirmaufzeichnung in Electron-Anwendungen nicht unterstützt, daher wird es unabhängig von dieser Einstellung immer im Browser geöffnet."
       },
       "minimizeOnClose": {
         "title": "Beim Schließen minimieren",
diff --git a/src/i18n/en.i18n.json b/src/i18n/en.i18n.json
index c3a6d2bc42..65b7b35b91 100644
--- a/src/i18n/en.i18n.json
+++ b/src/i18n/en.i18n.json
@@ -372,8 +372,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Video calls inside app",
-        "description": "Open video calls inside app window instead of browser. Google Meet and Jitsi calls can only open in browser.",
-        "masDescription": "This option is disabled when installed from the Mac App Store. For security reasons, video calls always open in the browser by default."
+        "description": "Open video calls inside app window instead of browser. Google Meet calls can only open in browser."
       },
       "minimizeOnClose": {
         "title": "Minimize on close",
diff --git a/src/i18n/es.i18n.json b/src/i18n/es.i18n.json
index 200827337b..c277339ce3 100644
--- a/src/i18n/es.i18n.json
+++ b/src/i18n/es.i18n.json
@@ -262,8 +262,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Abrir videollamada en la ventana de la aplicación",
-        "description": "Si está activado, la videollamada se abrirá en la ventana de la aplicación en lugar del navegador predeterminado. Sin embargo, para <strong>Google Meet</strong> y <strong>Jitsi</strong>, la grabación de pantalla no es compatible en aplicaciones Electron, por lo que siempre se abrirán en el navegador independientemente de esta configuración.",
-        "masDescription": "Esta opción está desactivada cuando se instala desde la Mac App Store; por razones de seguridad, las videollamadas se abrirán en el navegador de forma predeterminada."
+        "description": "Si está activado, la videollamada se abrirá en la ventana de la aplicación en lugar del navegador predeterminado. Sin embargo, para <strong>Google Meet</strong>, la grabación de pantalla no es compatible en aplicaciones Electron, por lo que siempre se abrirá en el navegador independientemente de esta configuración."
       },
       "minimizeOnClose": {
         "title": "Minimizar al cerrar",
diff --git a/src/i18n/fi.i18n.json b/src/i18n/fi.i18n.json
index 7d6b4ea111..5e8e62159c 100644
--- a/src/i18n/fi.i18n.json
+++ b/src/i18n/fi.i18n.json
@@ -250,8 +250,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Avaa videokeskustelu sovellusikkunaan",
-        "description": "Jos käytössä, videokeskustelu avautuu sovelluksen ikkunaan oletusselaimen sijaan. Kuitenkin <strong>Google Meet</strong> ja <strong>Jitsi</strong> -palveluissa ruuduntallennus ei ole tuettu Electron-sovelluksissa, joten ne avautuvat aina selaimessa tästä asetuksesta riippumatta.",
-        "masDescription": "Asetus ei ole käytössä, kun asennus on tehty Macin App Storesta. Suojaussyistä videokeskustelu avautuu oletusarvoisesti selaimeen."
+        "description": "Jos käytössä, videokeskustelu avautuu sovelluksen ikkunaan oletusselaimen sijaan. Kuitenkin <strong>Google Meet</strong> -palvelussa ruuduntallennus ei ole tuettu Electron-sovelluksissa, joten se avautuu aina selaimessa tästä asetuksesta riippumatta."
       },
       "minimizeOnClose": {
         "title": "Pienennä suljettaessa",
diff --git a/src/i18n/fr.i18n.json b/src/i18n/fr.i18n.json
index 7d31801576..a588ae67eb 100644
--- a/src/i18n/fr.i18n.json
+++ b/src/i18n/fr.i18n.json
@@ -250,8 +250,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Ouvrir le chat vidéo à l'aide de la fenêtre de l'application",
-        "description": "Si cette option est activée, le chat vidéo s'ouvrira dans la fenêtre de l'application au lieu du navigateur par défaut. Cependant, pour <strong>Google Meet</strong> et <strong>Jitsi</strong>, l'enregistrement d'écran n'est pas pris en charge dans les applications Electron, donc ils s'ouvriront toujours dans le navigateur, quel que soit ce paramètre.",
-        "masDescription": "Cette option est désactivée lorsqu'elle est installée à partir du Mac App Store, pour des raisons de sécurité, elle ouvrira le chat vidéo en utilisant le navigateur par défaut."
+        "description": "Si cette option est activée, le chat vidéo s'ouvrira dans la fenêtre de l'application au lieu du navigateur par défaut. Cependant, pour <strong>Google Meet</strong>, l'enregistrement d'écran n'est pas pris en charge dans les applications Electron, donc il s'ouvrira toujours dans le navigateur, quel que soit ce paramètre."
       },
       "minimizeOnClose": {
         "title": "Minimiser à la fermeture",
diff --git a/src/i18n/hu.i18n.json b/src/i18n/hu.i18n.json
index 6bb6e7be33..ca8dd99469 100644
--- a/src/i18n/hu.i18n.json
+++ b/src/i18n/hu.i18n.json
@@ -276,8 +276,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Videocsevegés megnyitása az alkalmazásablakban",
-        "description": "Ha engedélyezve van, akkor a videócsevegés az alkalmazás ablakában nyílik meg az alapértelmezett böngésző helyett. Azonban a <strong>Google Meet</strong> és a <strong>Jitsi</strong> esetében a képernyő rögzítése nem támogatott az Electron alkalmazásokban, így azok ettől a beállítástól függetlenül mindig a böngészőben nyílnak meg.",
-        "masDescription": "Ez a beállítás le van tiltva a Mac App Store-ból történő telepítéskor. Biztonsági okokból a videócsevegés alapértelmezetten mindig a böngészőben nyílik meg."
+        "description": "Ha engedélyezve van, akkor a videócsevegés az alkalmazás ablakában nyílik meg az alapértelmezett böngésző helyett. Azonban a <strong>Google Meet</strong> esetében a képernyő rögzítése nem támogatott az Electron alkalmazásokban, így az ettől a beállítástól függetlenül mindig a böngészőben nyílik meg."
       },
       "minimizeOnClose": {
         "title": "Kis méret bezáráskor",
diff --git a/src/i18n/no.i18n.json b/src/i18n/no.i18n.json
index f0da524222..599f527eee 100644
--- a/src/i18n/no.i18n.json
+++ b/src/i18n/no.i18n.json
@@ -283,8 +283,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Åpne videochat ved hjelp av applikasjonsvinduet",
-        "description": "Når innstilt, vil Videochat åpnes ved hjelp av et programvindu, ellers vil standardnettleseren brukes. <strong>Google Meet</strong> og <strong>Jitsi</strong> skjermopptak støttes ikke i Electron-applikasjoner, så denne konfigurasjonen endrer ikke anropsadferd, som åpnes i nettleseren.",
-        "masDescription": "Dette alternativet er deaktivert når det er installert fra Mac App Store, av sikkerhetsgrunner vil det åpne Video Chat ved å bruke nettleseren som standard."
+        "description": "Når innstilt, vil Videochat åpnes ved hjelp av et programvindu, ellers vil standardnettleseren brukes. <strong>Google Meet</strong> skjermopptak støttes ikke i Electron-applikasjoner, så denne konfigurasjonen endrer ikke anropsadferd, som åpnes i nettleseren."
       },
       "minimizeOnClose": {
         "title": "Minimer på nært hold",
diff --git a/src/i18n/pt-BR.i18n.json b/src/i18n/pt-BR.i18n.json
index 4c59fb978f..1786599c73 100644
--- a/src/i18n/pt-BR.i18n.json
+++ b/src/i18n/pt-BR.i18n.json
@@ -257,8 +257,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Abrir chat em video em uma janela da aplicação",
-        "description": "Se ativado, o Chat de Vídeo será aberto na janela do aplicativo em vez do navegador padrão. No entanto, para <strong>Google Meet</strong> e <strong>Jitsi</strong>, a gravação de tela não é suportada em aplicativos Electron, então eles sempre serão abertos no navegador independentemente desta configuração.",
-        "masDescription": "Esta opção esta desativada quando for instalado através da Mac App Store, por motivos de segurança o chat em video sera aberto usando o navegador por padrão."
+        "description": "Se ativado, o Chat de Vídeo será aberto na janela do aplicativo em vez do navegador padrão. No entanto, para <strong>Google Meet</strong>, a gravação de tela não é suportada em aplicativos Electron, então ele sempre será aberto no navegador independentemente desta configuração."
       },
       "minimizeOnClose": {
         "title": "Minimizar ao fechar",
diff --git a/src/i18n/ru.i18n.json b/src/i18n/ru.i18n.json
index d4091e11e0..3a21b11ea6 100644
--- a/src/i18n/ru.i18n.json
+++ b/src/i18n/ru.i18n.json
@@ -244,8 +244,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Открывать видеочат в окне приложения",
-        "description": "Если этот параметр включен, видеочат будет открываться в окне приложения вместо браузера по умолчанию. Однако для <strong>Google Meet</strong> и <strong>Jitsi</strong> запись экрана не поддерживается в приложениях Electron, поэтому они всегда будут открываться в браузере независимо от этой настройки.",
-        "masDescription": "Эта опция отключена при установке из Mac App Store, по соображениям безопасности окно видео чата будет открыто в браузере по умолчанию."
+        "description": "Если этот параметр включен, видеочат будет открываться в окне приложения вместо браузера по умолчанию. Однако для <strong>Google Meet</strong> запись экрана не поддерживается в приложениях Electron, поэтому он всегда будет открываться в браузере независимо от этой настройки."
       },
       "minimizeOnClose": {
         "title": "Свернуть в трей при закрытии",
diff --git a/src/i18n/sv.i18n.json b/src/i18n/sv.i18n.json
index 7ccacdfbba..cfe8ca7e9b 100644
--- a/src/i18n/sv.i18n.json
+++ b/src/i18n/sv.i18n.json
@@ -271,8 +271,7 @@
       },
       "internalVideoChatWindow": {
         "title": "Öppna videochatt i programfönstret",
-        "description": "Om den är aktiverad öppnas videochatten i programmets fönster i stället för i standardwebbläsaren. För <strong>Google Meet</strong> och <strong>Jitsi</strong> stöds dock inte skärminspelning i Electron-applikationer, så de kommer alltid att öppnas i webbläsaren oavsett denna inställning.",
-        "masDescription": "Detta alternativ är inaktiverat när det installeras från Mac App Store. Av säkerhetsskäl öppnas Video Chat alltid i webbläsaren som standard."
+        "description": "Om den är aktiverad öppnas videochatten i programmets fönster i stället för i standardwebbläsaren. För <strong>Google Meet</strong> stöds dock inte skärminspelning i Electron-applikationer, så det kommer alltid att öppnas i webbläsaren oavsett denna inställning."
       },
       "minimizeOnClose": {
         "title": "Minimera vid stängning",
diff --git a/src/i18n/zh-CN.i18n.json b/src/i18n/zh-CN.i18n.json
index 38af992475..dc4b66aad3 100644
--- a/src/i18n/zh-CN.i18n.json
+++ b/src/i18n/zh-CN.i18n.json
@@ -177,8 +177,7 @@
       },
       "internalVideoChatWindow": {
         "title": "在程序窗口中打开视频通话",
-        "description": "如果启用，视频通话将在应用程序窗口中打开，而不是在默认浏览器中打开。但是，对于<strong>Google Meet</strong>和<strong>Jitsi</strong>，Electron应用程序不支持屏幕录制，所以无论此设置如何，它们始终会在浏览器中打开。",
-        "masDescription": "从Mac App Store安装时此选项被禁用。出于安全原因，视频通话将始终默认在浏览器中打开。"
+        "description": "如果启用，视频通话将在应用程序窗口中打开，而不是在默认浏览器中打开。但是，对于<strong>Google Meet</strong>，Electron应用程序不支持屏幕录制，所以无论此设置如何，它始终会在浏览器中打开。"
       },
       "transparentWindow": {
         "title": "透明窗口效果",
diff --git a/src/injected.ts b/src/injected.ts
index 8b52337996..22070eb40a 100644
--- a/src/injected.ts
+++ b/src/injected.ts
@@ -744,7 +744,6 @@ const start = async () => {
           );
           window.open = (url, name, features = '') => {
             if (
-              !process.mas &&
               window.RocketChatDesktop.getInternalVideoChatWindowEnabled() &&
               typeof url === 'string' &&
               jitsiDomain.length > 0 &&
diff --git a/src/servers/preload/__tests__/internalVideoChatWindow.spec.ts b/src/servers/preload/__tests__/internalVideoChatWindow.spec.ts
index 1a3bc7f650..a877c37f0e 100644
--- a/src/servers/preload/__tests__/internalVideoChatWindow.spec.ts
+++ b/src/servers/preload/__tests__/internalVideoChatWindow.spec.ts
@@ -73,16 +73,20 @@ describe('servers/preload/internalVideoChatWindow', () => {
     expect(invokeMock).not.toHaveBeenCalled();
   });
 
-  it('falls back to external open when running from MAS build', () => {
+  it('opens the internal window when running from MAS build', () => {
     safeSelectMock.mockReturnValue(true);
     setProcessMas(true);
 
     openInternalVideoChatWindow('https://chat.example', {
-      providerName: 'googlemeet',
+      providerName: 'jitsi',
     });
 
-    expect(openExternalMock).toHaveBeenCalledWith('https://chat.example/');
-    expect(invokeMock).not.toHaveBeenCalled();
+    expect(invokeMock).toHaveBeenCalledWith(
+      'video-call-window/open-window',
+      'https://chat.example/',
+      { providerName: 'jitsi' }
+    );
+    expect(openExternalMock).not.toHaveBeenCalled();
   });
 
   it('opens jitsi calls on the dedicated invoke path', () => {
diff --git a/src/servers/preload/internalVideoChatWindow.ts b/src/servers/preload/internalVideoChatWindow.ts
index b74095ffb9..2e3a244b72 100644
--- a/src/servers/preload/internalVideoChatWindow.ts
+++ b/src/servers/preload/internalVideoChatWindow.ts
@@ -21,7 +21,7 @@ export const openInternalVideoChatWindow = (
   if (!allowedProtocols.includes(validUrl.protocol)) {
     return;
   }
-  if (!process.mas && getInternalVideoChatWindowEnabled()) {
+  if (getInternalVideoChatWindowEnabled()) {
     switch (options?.providerName) {
       case 'jitsi':
         // window.open(validUrl.href, 'Video Call', 'scrollbars=true');
diff --git a/src/settingsWindow/sections/VideoCallsSection.tsx b/src/settingsWindow/sections/VideoCallsSection.tsx
index 853d53bea4..e4ecab146a 100644
--- a/src/settingsWindow/sections/VideoCallsSection.tsx
+++ b/src/settingsWindow/sections/VideoCallsSection.tsx
@@ -11,7 +11,7 @@ export const VideoCallsSection = () => (
       <InternalVideoChatWindow />
       <VideoCallWindowPersistence />
       {process.platform === 'win32' && <ScreenCaptureFallback />}
-      {!process.mas && <ClearPermittedScreenCaptureServers />}
+      <ClearPermittedScreenCaptureServers />
     </FieldGroup>
   </Box>
 );
diff --git a/src/ui/components/SettingsView/features/InternalVideoChatWindow.tsx b/src/ui/components/SettingsView/features/InternalVideoChatWindow.tsx
index 3a328681fd..796de8874b 100644
--- a/src/ui/components/SettingsView/features/InternalVideoChatWindow.tsx
+++ b/src/ui/components/SettingsView/features/InternalVideoChatWindow.tsx
@@ -39,14 +39,9 @@ export const InternalVideoChatWindow = (
     <ToggleField
       id={isInternalVideoChatWindowEnabledId}
       label={t('settings.options.internalVideoChatWindow.title')}
-      description={
-        process.mas
-          ? t('settings.options.internalVideoChatWindow.masDescription')
-          : t('settings.options.internalVideoChatWindow.description')
-      }
+      description={t('settings.options.internalVideoChatWindow.description')}
       checked={isInternalVideoChatWindowEnabled}
       onChange={handleChange}
-      disabled={process.mas}
       className={props.className}
     />
   );
diff --git a/src/videoCallWindow/ipc.ts b/src/videoCallWindow/ipc.ts
index 95d679dd31..1d1e33a8d9 100644
--- a/src/videoCallWindow/ipc.ts
+++ b/src/videoCallWindow/ipc.ts
@@ -610,6 +610,52 @@ const setupWebviewHandlers = (webContents: WebContents) => {
     });
 };
 
+/**
+ * Whether two URLs open the same conference: the same page, whatever the
+ * fragment. Unparseable URLs are never the same.
+ */
+export const isSameConferenceUrl = (a: string, b: string): boolean => {
+  try {
+    const first = new URL(a);
+    const second = new URL(b);
+    return (
+      first.origin === second.origin &&
+      first.pathname === second.pathname &&
+      first.search === second.search
+    );
+  } catch {
+    return false;
+  }
+};
+
+/**
+ * What the call window's webview shows now. It can have moved on in-page from
+ * the URL the window was opened for: the web client's conference start page
+ * replaces its own address with the conference's once the conference exists.
+ */
+const getVideoCallWebviewUrl = (): string | null => {
+  const host = videoCallWindow?.webContents;
+  if (!host) {
+    return null;
+  }
+
+  const guest = webContents
+    .getAllWebContents()
+    .find((wc: WebContents) => wc.hostWebContents === host);
+
+  return guest && !guest.isDestroyed() ? guest.getURL() : null;
+};
+
+/**
+ * Whether the open call window is already on the conference at `url`, by the
+ * URL it was opened for or by what it shows now. Reopening it would tear the
+ * call down and join it again, so the others in it see this user freeze.
+ */
+const isShowingConference = (url: string): boolean =>
+  [activeCall?.url, getVideoCallWebviewUrl()].some(
+    (shown) => !!shown && isSameConferenceUrl(shown, url)
+  );
+
 // eslint-disable-next-line complexity
 const openVideoCallWindow = async (
   _wc: WebContents,
@@ -627,7 +673,7 @@ const openVideoCallWindow = async (
     videoCallWindow &&
     !videoCallWindow.isDestroyed() &&
     !isVideoCallWindowDestroying &&
-    activeCall?.url === url
+    isShowingConference(url)
   ) {
     console.log(
       'Video call window: same conference already open, focusing existing window'
diff --git a/src/videoCallWindow/main/ipc.main.spec.ts b/src/videoCallWindow/main/ipc.main.spec.ts
index dd7a5389ee..ebd1245943 100644
--- a/src/videoCallWindow/main/ipc.main.spec.ts
+++ b/src/videoCallWindow/main/ipc.main.spec.ts
@@ -1319,4 +1319,108 @@ describe('videoCallWindow/ipc — PR #3359 hardening', () => {
       expect(guest.session.setPermissionRequestHandler).not.toHaveBeenCalled();
     });
   });
+
+  // -------------------------------------------------------------------------
+  // open — the same conference focuses the open window instead of recreating it
+  // -------------------------------------------------------------------------
+  describe('reopening the conference the window is already on', () => {
+    const startUrl = 'https://chat.example/conference/new?rid=room-1';
+    const conferenceUrl = 'https://chat.example/conference/call-1';
+
+    /** The webview inside the open call window, showing `shown`. */
+    const showInWebview = async (shown: string) => {
+      const { webContents } = (await import('electron')) as any;
+      const host = createdWindows[0].webContents;
+      webContents.getAllWebContents.mockReturnValue([
+        {
+          hostWebContents: host,
+          getURL: jest.fn(() => shown),
+          isDestroyed: jest.fn(() => false),
+        },
+      ]);
+    };
+
+    it('focuses the window opened for the same URL', async () => {
+      getServerUrlByWebContentsId.mockReturnValue('https://chat.example');
+      const { openWindow } = await loadModule();
+      await open(openWindow, makeCallerWc(1), conferenceUrl);
+
+      await open(openWindow, makeCallerWc(1), conferenceUrl);
+
+      expect(createdWindows).toHaveLength(1);
+      expect((createdWindows[0] as any).close).not.toHaveBeenCalled();
+      expect((createdWindows[0] as any).focus).toHaveBeenCalled();
+    });
+
+    // A call the user starts opens at the start page, which replaces its own
+    // address with the conference's once the conference exists — so the URL the
+    // window was opened for no longer names the call it is in.
+    it('focuses the window whose webview has moved in-page to the conference', async () => {
+      getServerUrlByWebContentsId.mockReturnValue('https://chat.example');
+      const { openWindow } = await loadModule();
+      await open(openWindow, makeCallerWc(1), startUrl);
+      await showInWebview(conferenceUrl);
+
+      await open(openWindow, makeCallerWc(1), conferenceUrl);
+
+      expect(createdWindows).toHaveLength(1);
+      expect((createdWindows[0] as any).close).not.toHaveBeenCalled();
+      expect((createdWindows[0] as any).focus).toHaveBeenCalled();
+    });
+
+    it('replaces the window for a different conference', async () => {
+      getServerUrlByWebContentsId.mockReturnValue('https://chat.example');
+      const { openWindow } = await loadModule();
+      await open(openWindow, makeCallerWc(1), startUrl);
+      await showInWebview(conferenceUrl);
+
+      await open(
+        openWindow,
+        makeCallerWc(1),
+        'https://chat.example/conference/call-2'
+      );
+
+      expect((createdWindows[0] as any).close).toHaveBeenCalled();
+      expect(createdWindows).toHaveLength(2);
+    });
+  });
+
+  describe('isSameConferenceUrl', () => {
+    it.each([
+      [
+        'a different fragment',
+        'https://meet.example/room#config.startWithAudioMuted=true',
+        'https://meet.example/room',
+        true,
+      ],
+      [
+        'a different query',
+        'https://chat.example/conference/new?rid=room-1',
+        'https://chat.example/conference/new?rid=room-2',
+        false,
+      ],
+      [
+        'a different path',
+        'https://chat.example/conference/call-1',
+        'https://chat.example/conference/call-2',
+        false,
+      ],
+      [
+        'a different origin',
+        'https://chat.example/conference/call-1',
+        'https://other.example/conference/call-1',
+        false,
+      ],
+      [
+        'an unparseable URL',
+        'not a url',
+        'https://chat.example/conference/call-1',
+        false,
+      ],
+    ])('compares URLs with %s', async (_case, a, b, expected) => {
+      const { mod } = await loadModule();
+
+      expect(mod.isSameConferenceUrl(a, b)).toBe(expected);
+    });
+  });
 });