feat(clerk-js): Add enhanced poller to main browser build

.changeset/curly-dingos-pay.md

@@ -0,0 +1,6 @@
+---
+'@clerk/clerk-js': minor
+---
+
+Optimized session token poller to share token with other open tabs
+

integration/tests/session-token-cache/single-session.test.ts

@@ -11,7 +11,7 @@ import { createTestUtils, testAgainstRunningApps } from '../../testUtils';
  * token fetches in one tab are automatically broadcast and cached in other tabs,
  * eliminating redundant network requests.
  */
-testAgainstRunningApps({ withEnv: [appConfigs.envs.withBroadcastChannel] })(
+testAgainstRunningApps({ withEnv: [appConfigs.envs.withEmailCodes] })(
   'MemoryTokenCache Multi-Tab Integration @generic',
   ({ app }) => {
     test.describe.configure({ mode: 'serial' });

packages/clerk-js/src/core/tokenCache.ts

@@ -138,7 +138,7 @@ const generateTabId = (): string => {
 /**
  * Creates an in-memory token cache with optional BroadcastChannel synchronization across tabs.
  * Automatically manages token expiration and cleanup via scheduled timeouts.
- * BroadcastChannel support is enabled only in the channel build variant.
+ * BroadcastChannel support is enabled whenever the environment provides it.
  */
 const MemoryTokenCache = (prefix = KEY_PREFIX): TokenCache => {
   const cache = new Map<string, TokenCacheValue>();
@@ -147,21 +147,19 @@ const MemoryTokenCache = (prefix = KEY_PREFIX): TokenCache => {
   let broadcastChannel: BroadcastChannel | null = null;
 
   const ensureBroadcastChannel = (): BroadcastChannel | null => {
-    if (!__BUILD_VARIANT_CHANNEL__) {
-      return null;
-    }
-
     if (broadcastChannel) {
       return broadcastChannel;
     }
 
-    if (typeof BroadcastChannel !== 'undefined') {
-      broadcastChannel = new BroadcastChannel('clerk:session_token');
-      broadcastChannel.addEventListener('message', (e: MessageEvent<SessionTokenEvent>) => {
-        void handleBroadcastMessage(e);
-      });
+    if (typeof BroadcastChannel === 'undefined') {
+      return null;
     }
 
+    broadcastChannel = new BroadcastChannel('clerk:session_token');
+    broadcastChannel.addEventListener('message', (e: MessageEvent<SessionTokenEvent>) => {
+      void handleBroadcastMessage(e);
+    });
+
     return broadcastChannel;
   };