fix(clerk-js): resolve offline mode crash by enhancing error handling and cache fallback

Author: chriscanin

.changeset/fix-offline-mode-resource-cache.md

@@ -0,0 +1,6 @@
+---
+'@clerk/clerk-js': patch
+'@clerk/clerk-expo': patch
+---
+
+Fix offline mode crash when using `__experimental_resourceCache` by handling missing `protect_config` field from FAPI response and broadening error handling to trigger cache fallback for non-network errors.

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

@@ -2741,8 +2741,7 @@ export class Clerk implements ClerkInterface {
   };
 
   private shouldFallbackToCachedResources = (): boolean => {
-    const hasCacheFunction = !!this.__internal_getCachedResources;
-    return hasCacheFunction;
+    return !!this.__internal_getCachedResources;
   };
 
   #loadInNonStandardBrowser = async (): Promise<void> => {
@@ -2755,9 +2754,11 @@ export class Clerk implements ClerkInterface {
         Client.getOrCreateInstance().fetch({ fetchMaxTries }),
       ]);
     } catch (err) {
-      const shouldFallback =
-        this.shouldFallbackToCachedResources() &&
-        ((isClerkRuntimeError(err) && err.code === 'network_error') || !isClerkRuntimeError(err));
+      const isNetworkError =
+        (isClerkRuntimeError(err) && err.code === 'network_error') ||
+        (err instanceof Error && err.message?.includes('Network error at'));
+
+      const shouldFallback = this.shouldFallbackToCachedResources() && isNetworkError;
 
       if (shouldFallback) {
         const cachedResources = await this.__internal_getCachedResources?.();