fix(clerk-js): Invalidate server cache for after-auth custom flows (#6425)

Author: LauraBeatris

.changeset/modern-clocks-sip.md

@@ -0,0 +1,5 @@
+---
+'@clerk/clerk-js': patch
+---
+
+Fix server-side session cache not being invalidated for after-auth custom flows

packages/clerk-js/bundlewatch.config.json

@@ -1,7 +1,7 @@
 {
   "files": [
     { "path": "./dist/clerk.js", "maxSize": "618KB" },
-    { "path": "./dist/clerk.browser.js", "maxSize": "72.2KB" },
+    { "path": "./dist/clerk.browser.js", "maxSize": "74KB" },
     { "path": "./dist/clerk.legacy.browser.js", "maxSize": "115.08KB" },
     { "path": "./dist/clerk.headless*.js", "maxSize": "55KB" },
     { "path": "./dist/ui-common*.js", "maxSize": "113KB" },

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

@@ -1325,6 +1325,29 @@ export class Clerk implements ClerkInterface {
   };
 
   #handlePendingSession = async (session: PendingSessionResource) => {
+    /**
+     * Do not revalidate server cache when `setActive` is called with a pending
+     * session within components, to avoid flash of content and unmount during
+     * internal navigation
+     */
+    const shouldInvalidateCache = !this.#componentNavigationContext;
+
+    const onBeforeSetActive: SetActiveHook =
+      shouldInvalidateCache &&
+      typeof window !== 'undefined' &&
+      typeof window.__unstable__onBeforeSetActive === 'function'
+        ? window.__unstable__onBeforeSetActive
+        : noop;
+
+    const onAfterSetActive: SetActiveHook =
+      shouldInvalidateCache &&
+      typeof window !== 'undefined' &&
+      typeof window.__unstable__onAfterSetActive === 'function'
+        ? window.__unstable__onAfterSetActive
+        : noop;
+
+    await onBeforeSetActive();
+
     if (!this.environment) {
       return;
     }
@@ -1358,6 +1381,8 @@ export class Clerk implements ClerkInterface {
 
     this.#setAccessors(session);
     this.#emit();
+
+    await onAfterSetActive();
   };
 
   public __internal_navigateToTaskIfAvailable = async ({