diff --git a/plugins/fusion-plugin-reports/src/dashboard/test-setup.ts b/plugins/fusion-plugin-reports/src/dashboard/test-setup.ts
index 9d53dd2c3..a90051000 100644
--- a/plugins/fusion-plugin-reports/src/dashboard/test-setup.ts
+++ b/plugins/fusion-plugin-reports/src/dashboard/test-setup.ts
@@ -1,5 +1,13 @@
 import "@testing-library/jest-dom/vitest";
-import { vi } from "vitest";
+import { cleanup } from "@testing-library/react";
+import { afterEach, vi } from "vitest";
+
+// @testing-library/react only auto-registers cleanup when vitest globals are
+// enabled. We don't enable globals here, so we wire it manually — otherwise
+// React leaves the test tree mounted, its scheduler fires a deferred update
+// via setImmediate after the jsdom environment is torn down, and the suite
+// fails with "ReferenceError: window is not defined".
+afterEach(() => cleanup());
 
 if (typeof window !== "undefined") {
   Object.defineProperty(window, "matchMedia", {