diff --git a/app/dags/page.tsx b/app/dags/page.tsx
index 98afd8e..c863302 100644
--- a/app/dags/page.tsx
+++ b/app/dags/page.tsx
@@ -78,7 +78,8 @@ export default async function DAGs({
           detail="Fresh fleet data requires Airflow credentials, Upstash Redis, and the scheduled refresh. Page requests never scan the production fleet."
         />
       )}
-      <form method="get" className="filter-form">
+      {/* Stops the browser restoring an unsubmitted selection on Back. */}
+      <form method="get" className="filter-form" autoComplete="off">
         <label>
           Search DAGs
           <input
diff --git a/tests/dashboard.e2e.ts b/tests/dashboard.e2e.ts
index f3520f1..1790824 100644
--- a/tests/dashboard.e2e.ts
+++ b/tests/dashboard.e2e.ts
@@ -70,6 +70,13 @@ test("review and DAG filters use URL state", async ({
     .selectOption({ value: "failed" });
   await screen.getByRole("button", "Filter DAGs").tap();
   await expect(browser).toHaveURL(/q=church.*state=failed/);
+  const runState = screen.getByLabel("Run state", { exact: true });
+  await runState.selectOption({ value: "no_runs" });
+  await screen.getByRole("button", "Filter DAGs").tap();
+  await expect(browser).toHaveURL(/state=no_runs/);
+  await browser.back();
+  await expect(browser).toHaveURL(/state=failed/);
+  await expect(runState).toHaveValue("failed");
 });
 test("mobile navigation stays usable", async ({ app, browser, screen }) => {
   await browser.setViewport({ width: 390, height: 844 });