diff --git a/desktop/src/preload.js b/desktop/src/preload.js
--- a/desktop/src/preload.js
+++ b/desktop/src/preload.js
@@ -22,6 +22,7 @@
       ipcRenderer.removeListener('on-new-version-available', withEvent);
   },
   updateToNewVersion: () => ipcRenderer.send('update-to-new-version'),
+  platform: { win32: 'windows', darwin: 'macos' }[process.platform],
 };
 
 contextBridge.exposeInMainWorld('electronContextBridge', bridge);
diff --git a/keyserver/src/responders/website-responders.js b/keyserver/src/responders/website-responders.js
--- a/keyserver/src/responders/website-responders.js
+++ b/keyserver/src/responders/website-responders.js
@@ -384,7 +384,7 @@
     windowDimensions: { width: 0, height: 0 },
     baseHref,
     connection: {
-      ...defaultConnectionInfo('web', viewer.timeZone),
+      ...defaultConnectionInfo(viewer.platform ?? 'web', viewer.timeZone),
       actualizedCalendarQuery: calendarQuery,
     },
     watchedThreadIDs: [],
diff --git a/keyserver/src/socket/socket.js b/keyserver/src/socket/socket.js
--- a/keyserver/src/socket/socket.js
+++ b/keyserver/src/socket/socket.js
@@ -17,6 +17,7 @@
 import { endpointIsSocketSafe } from 'lib/types/endpoints.js';
 import { defaultNumberPerThread } from 'lib/types/message-types.js';
 import { redisMessageTypes, type RedisMessage } from 'lib/types/redis-types.js';
+import { serverRequestTypes } from 'lib/types/request-types.js';
 import {
   cookieSources,
   sessionCheckFrequency,
@@ -455,6 +456,16 @@
       ),
     };
 
+    if (
+      viewer.userAgent?.includes('Electron') &&
+      viewer.platform === 'web' &&
+      !serverRequests.find(
+        request => request.type === serverRequestTypes.PLATFORM_DETAILS,
+      )
+    ) {
+      serverRequests.push({ type: serverRequestTypes.PLATFORM_DETAILS });
+    }
+
     if (!sessionInitializationResult.sessionContinued) {
       const [threadsResult, entriesResult, currentUserInfo, knownUserInfos] =
         await Promise.all([
diff --git a/lib/types/device-types.js b/lib/types/device-types.js
--- a/lib/types/device-types.js
+++ b/lib/types/device-types.js
@@ -3,7 +3,7 @@
 import invariant from 'invariant';
 
 export type DeviceType = 'ios' | 'android';
-export type Platform = DeviceType | 'web';
+export type Platform = DeviceType | 'web' | 'windows' | 'macos';
 
 export function isDeviceType(platform: ?string): boolean {
   return platform === 'ios' || platform === 'android';
@@ -18,7 +18,7 @@
 }
 
 export function isWebPlatform(platform: ?string): boolean {
-  return platform === 'web';
+  return platform === 'web' || platform === 'windows' || platform === 'macos';
 }
 
 export type DeviceTokenUpdateRequest = {
diff --git a/lib/types/electron-types.js b/lib/types/electron-types.js
--- a/lib/types/electron-types.js
+++ b/lib/types/electron-types.js
@@ -17,4 +17,5 @@
   // Returns a callback that you can call to remove the listener
   +onNewVersionAvailable?: OnNewVersionAvailableListener => () => void,
   +updateToNewVersion?: () => void,
+  +platform?: 'windows' | 'macos',
 };
diff --git a/lib/utils/validation-utils.js b/lib/utils/validation-utils.js
--- a/lib/utils/validation-utils.js
+++ b/lib/utils/validation-utils.js
@@ -50,7 +50,13 @@
 
 const tDate: TRegex = tRegex(/^[0-9]{4}-[0-1][0-9]-[0-3][0-9]$/);
 const tColor: TRegex = tRegex(validHexColorRegex); // we don't include # char
-const tPlatform: TEnums = t.enums.of(['ios', 'android', 'web']);
+const tPlatform: TEnums = t.enums.of([
+  'ios',
+  'android',
+  'web',
+  'windows',
+  'macos',
+]);
 const tDeviceType: TEnums = t.enums.of(['ios', 'android']);
 const tPlatformDetails: TInterface = tShape({
   platform: tPlatform,
diff --git a/web/app.react.js b/web/app.react.js
--- a/web/app.react.js
+++ b/web/app.react.js
@@ -77,7 +77,7 @@
   setSessionIDOnRequest: true,
   // Never reset the calendar range
   calendarRangeInactivityLimit: null,
-  platformDetails: { platform: 'web' },
+  platformDetails: { platform: electron?.platform ?? 'web' },
 });
 
 type BaseProps = {