diff --git a/frontend/e2e/lang.spec.ts b/frontend/e2e/lang.spec.ts
index 04294a98..9034b4c1 100644
--- a/frontend/e2e/lang.spec.ts
+++ b/frontend/e2e/lang.spec.ts
@@ -10,6 +10,7 @@ test.describe('Language selector', () => {
 
 	test('switching to EN translates the navigation', async ({ page }) => {
 		await page.goto('/');
+		await page.waitForSelector('[data-hydrated]');
 		await page.getByRole('banner').getByRole('button', { name: 'EN', exact: true }).click();
 		await expect(page.getByRole('navigation').getByRole('link', { name: 'Documents' })).toBeVisible();
 		await expect(page.getByRole('navigation').getByRole('link', { name: 'Persons' })).toBeVisible();
@@ -17,6 +18,7 @@ test.describe('Language selector', () => {
 
 	test('language choice persists after navigation', async ({ page }) => {
 		await page.goto('/');
+		await page.waitForSelector('[data-hydrated]');
 		await page.getByRole('banner').getByRole('button', { name: 'EN', exact: true }).click();
 		await page.goto('/persons');
 		await expect(page.getByRole('navigation').getByRole('link', { name: 'Documents' })).toBeVisible();
@@ -24,6 +26,7 @@ test.describe('Language selector', () => {
 
 	test('switching back to DE restores German', async ({ page }) => {
 		await page.goto('/');
+		await page.waitForSelector('[data-hydrated]');
 		await page.getByRole('banner').getByRole('button', { name: 'EN', exact: true }).click();
 		await page.getByRole('banner').getByRole('button', { name: 'DE', exact: true }).click();
 		await expect(page.getByRole('navigation').getByRole('link', { name: 'Dokumente' })).toBeVisible();
diff --git a/frontend/e2e/persons.spec.ts b/frontend/e2e/persons.spec.ts
index a6c689bd..c6072347 100644
--- a/frontend/e2e/persons.spec.ts
+++ b/frontend/e2e/persons.spec.ts
@@ -87,6 +87,7 @@ test.describe('Conversations', () => {
 
 	test('sort toggle changes the button label', async ({ page }) => {
 		await page.goto('/conversations');
+		await page.waitForSelector('[data-hydrated]');
 		const btn = page.getByRole('button', { name: /Sortierung/i });
 		await expect(btn).toContainText('Neueste zuerst');
 		await btn.click();
diff --git a/frontend/src/hooks.server.ts b/frontend/src/hooks.server.ts
index 02275849..a88994f9 100644
--- a/frontend/src/hooks.server.ts
+++ b/frontend/src/hooks.server.ts
@@ -11,7 +11,7 @@ const handleLocaleDetection: Handle = ({ event, resolve }) => {
 	if (!event.cookies.get(cookieName)) {
 		const locale = detectLocale(event.request.headers.get('accept-language') ?? '');
 		if (locale) {
-			event.cookies.set(cookieName, locale, { path: '/', sameSite: 'lax', maxAge: cookieMaxAge });
+			event.cookies.set(cookieName, locale, { path: '/', sameSite: 'lax', maxAge: cookieMaxAge, httpOnly: false });
 		}
 	}
 	return resolve(event);