diff --git a/frontend/src/hooks.server.ts b/frontend/src/hooks.server.ts
index 5fe167c1..de71e2b9 100644
--- a/frontend/src/hooks.server.ts
+++ b/frontend/src/hooks.server.ts
@@ -1,5 +1,5 @@
 import * as Sentry from '@sentry/sveltekit';
-import { redirect, type Handle, type HandleFetch } from '@sveltejs/kit';
+import { isRedirect, redirect, type Handle, type HandleFetch } from '@sveltejs/kit';
 import { paraglideMiddleware } from '$lib/paraglide/server';
 import { sequence } from '@sveltejs/kit/hooks';
 import { env } from 'process';
@@ -87,10 +87,9 @@ const userGroup: Handle = async ({ event, resolve }) => {
 			}
 		}
 	} catch (error) {
-		// Don't swallow SvelteKit redirects — they're thrown as objects with a `status` field.
-		if (error instanceof Object && 'status' in error && 'location' in error) {
-			throw error;
-		}
+		// Re-throw SvelteKit redirects (e.g. the /login?reason=expired throw above)
+		// using the official guard rather than duck-typing on the error shape.
+		if (isRedirect(error)) throw error;
 		console.error('Error fetching user in hook:', error);
 	}