diff --git a/frontend/src/lib/activity/ChronikFuerDichBox.svelte.test.ts b/frontend/src/lib/activity/ChronikFuerDichBox.svelte.test.ts
new file mode 100644
index 00000000..6b887a86
--- /dev/null
+++ b/frontend/src/lib/activity/ChronikFuerDichBox.svelte.test.ts
@@ -0,0 +1,132 @@
+import { describe, it, expect, vi, afterEach } from 'vitest';
+import { cleanup, render } from 'vitest-browser-svelte';
+import { page } from 'vitest/browser';
+import ChronikFuerDichBox from './ChronikFuerDichBox.svelte';
+import type { NotificationItem } from '$lib/notification/notifications';
+
+afterEach(cleanup);
+
+const mention = (overrides: Partial<NotificationItem> = {}): NotificationItem => ({
+	id: 'n-1',
+	type: 'MENTION',
+	documentId: 'doc-1',
+	referenceId: 'ref-1',
+	annotationId: null,
+	read: false,
+	createdAt: new Date().toISOString(),
+	actorName: 'Anna',
+	documentTitle: 'Brief 1899',
+	...overrides
+});
+
+describe('ChronikFuerDichBox', () => {
+	it('renders the inbox-zero state when there are no unread', async () => {
+		render(ChronikFuerDichBox, {
+			props: { unread: [], onMarkRead: () => {}, onMarkAllRead: () => {} }
+		});
+
+		await expect.element(page.getByText(/keine neuen erwähnungen/i)).toBeVisible();
+		const link = document.querySelector('a[href="/aktivitaeten?filter=fuer-dich"]');
+		expect(link).not.toBeNull();
+	});
+
+	it('renders the count badge with the unread count', async () => {
+		render(ChronikFuerDichBox, {
+			props: {
+				unread: [mention(), mention({ id: 'n-2' }), mention({ id: 'n-3' })],
+				onMarkRead: () => {},
+				onMarkAllRead: () => {}
+			}
+		});
+
+		const badge = document.querySelector('[data-testid="chronik-fuerdich-count"]');
+		expect(badge?.textContent).toContain('3');
+	});
+
+	it('uses the @ glyph for MENTION and ↩ for REPLY', async () => {
+		render(ChronikFuerDichBox, {
+			props: {
+				unread: [mention({ id: 'n-m', type: 'MENTION' }), mention({ id: 'n-r', type: 'REPLY' })],
+				onMarkRead: () => {},
+				onMarkAllRead: () => {}
+			}
+		});
+
+		const items = document.querySelectorAll('ul[role="list"] li');
+		expect(items.length).toBe(2);
+		expect(items[0].textContent).toContain('@');
+		expect(items[1].textContent).toContain('↩');
+	});
+
+	it('renders MENTION verb text from paraglide messages', async () => {
+		render(ChronikFuerDichBox, {
+			props: {
+				unread: [mention({ actorName: 'Bertha' })],
+				onMarkRead: () => {},
+				onMarkAllRead: () => {}
+			}
+		});
+
+		await expect
+			.element(page.getByText(/bertha hat dich in einem kommentar erwähnt/i))
+			.toBeVisible();
+	});
+
+	it('renders REPLY verb text from paraglide messages', async () => {
+		render(ChronikFuerDichBox, {
+			props: {
+				unread: [mention({ type: 'REPLY', actorName: 'Carl' })],
+				onMarkRead: () => {},
+				onMarkAllRead: () => {}
+			}
+		});
+
+		await expect
+			.element(page.getByText(/carl hat auf deinen kommentar geantwortet/i))
+			.toBeVisible();
+	});
+
+	it('calls onMarkRead with the notification when its dismiss button is clicked', async () => {
+		const onMarkRead = vi.fn();
+		const item = mention({ id: 'n-7' });
+		render(ChronikFuerDichBox, {
+			props: { unread: [item], onMarkRead, onMarkAllRead: () => {} }
+		});
+
+		const dismiss = document.querySelector(
+			'[data-testid="chronik-fuerdich-dismiss"]'
+		) as HTMLElement;
+		dismiss.click();
+
+		expect(onMarkRead).toHaveBeenCalledWith(item);
+	});
+
+	it('calls onMarkAllRead when the mark-all-read button is clicked', async () => {
+		const onMarkAllRead = vi.fn();
+		render(ChronikFuerDichBox, {
+			props: {
+				unread: [mention()],
+				onMarkRead: () => {},
+				onMarkAllRead
+			}
+		});
+
+		const btn = document.querySelector('[data-testid="chronik-mark-all-read"]') as HTMLElement;
+		btn.click();
+
+		expect(onMarkAllRead).toHaveBeenCalledOnce();
+	});
+
+	it('builds a deep-link href to the comment for each notification', async () => {
+		render(ChronikFuerDichBox, {
+			props: {
+				unread: [mention({ documentId: 'doc-x', referenceId: 'ref-y', annotationId: null })],
+				onMarkRead: () => {},
+				onMarkAllRead: () => {}
+			}
+		});
+
+		const link = document.querySelector('ul[role="list"] li a') as HTMLAnchorElement;
+		expect(link.getAttribute('href')).toContain('doc-x');
+	});
+});