diff --git a/vitestSetup.ts b/vitestSetup.ts
index aa9bedb..1c98e44 100644
--- a/vitestSetup.ts
+++ b/vitestSetup.ts
@@ -1,4 +1,11 @@
-import { vi } from 'vitest'
+import { cleanup } from '@testing-library/react'
+import { afterEach, vi } from 'vitest'
+
+// Vitest globals are intentionally disabled, so React Testing Library cannot
+// auto-register its own cleanup hook. Unmount every rendered tree before the
+// JSDOM environment is torn down; pending React 19 transitions can otherwise
+// try to commit against an already-disposed window.
+afterEach(cleanup)
 
 vi.mock('next/router', () => require('next-router-mock'))
 vi.mock('@/i18n/routing', () => ({