diff --git a/libs/portal/stalker/data-access/src/lib/background-interval.spec.ts b/libs/portal/stalker/data-access/src/lib/background-interval.spec.ts
index da95a2d05..dc05d6505 100644
--- a/libs/portal/stalker/data-access/src/lib/background-interval.spec.ts
+++ b/libs/portal/stalker/data-access/src/lib/background-interval.spec.ts
@@ -98,4 +98,19 @@ describe('createBackgroundInterval', () => {
         jest.advanceTimersByTime(60_000);
         expect(callback).toHaveBeenCalledTimes(1);
     });
+
+    it('stays stopped when a worker error arrives after stop', () => {
+        scope.Worker = FakeWorker;
+        const callback = jest.fn();
+
+        const stop = createBackgroundInterval(callback, 30_000);
+        const [worker] = FakeWorker.instances;
+        const lateError = worker.onerror;
+        stop();
+        lateError?.(new Event('error'));
+
+        jest.advanceTimersByTime(90_000);
+        expect(callback).not.toHaveBeenCalled();
+        expect(jest.getTimerCount()).toBe(0);
+    });
 });
diff --git a/libs/portal/stalker/data-access/src/lib/background-interval.ts b/libs/portal/stalker/data-access/src/lib/background-interval.ts
index f10f30225..c51950eec 100644
--- a/libs/portal/stalker/data-access/src/lib/background-interval.ts
+++ b/libs/portal/stalker/data-access/src/lib/background-interval.ts
@@ -24,7 +24,10 @@ export function createBackgroundInterval(
     periodMs: number
 ): () => void {
     let fallback: ReturnType<typeof setInterval> | undefined;
+    let stopped = false;
     const startFallback = () => {
+        // A worker error that arrives after stop() must not revive the tick.
+        if (stopped) return;
         fallback ??= setInterval(callback, periodMs);
     };
     const ticker = startTickerWorker();
@@ -45,6 +48,11 @@ export function createBackgroundInterval(
         startFallback();
     }
     return () => {
+        stopped = true;
+        if (ticker) {
+            ticker.worker.onmessage = null;
+            ticker.worker.onerror = null;
+        }
         stopWorker();
         if (fallback !== undefined) clearInterval(fallback);
     };