diff --git a/src/app/auth/login/__tests__/page.browser.test.tsx b/src/app/auth/login/__tests__/page.browser.test.tsx
index c4b163fde..234cbcf7d 100644
--- a/src/app/auth/login/__tests__/page.browser.test.tsx
+++ b/src/app/auth/login/__tests__/page.browser.test.tsx
@@ -63,6 +63,21 @@ describe("sign-in page, single sign-on", () => {
   });
 });
 
+describe("sign-in page, single sign-on with a stuck cache", () => {
+  it("still leaves for the identity provider when the wipe never settles", async () => {
+    // WebKit can leave an IndexedDB open hanging after the app returns from
+    // the background; the button did nothing then.
+    clearOffline.mockImplementationOnce(() => new Promise(() => {}));
+    const { screen } = await renderWithApp(<LoginPage />, { user: null });
+    await screen.getByRole("button", { name: "Example ID" }).click();
+
+    await expect
+      .poll(() => loadDocument.mock.calls.length, { timeout: 4000 })
+      .toBe(1);
+    expect(clearOffline).toHaveBeenCalledTimes(1);
+  });
+});
+
 describe("sign-in page, password", () => {
   it("replaces itself with the page asked for", async () => {
     api.on("POST", "/api/auth/login", { data: { id: "signed-in" } });
diff --git a/src/app/auth/login/page.tsx b/src/app/auth/login/page.tsx
index bcc84657b..3d5b3e9ed 100644
--- a/src/app/auth/login/page.tsx
+++ b/src/app/auth/login/page.tsx
@@ -24,6 +24,7 @@ import { OIDC_MFA_COOKIE, OIDC_MFA_COOKIE_PATH } from "@/lib/auth/oidc-cookie";
 import { isDashboardSnapshotEnabled } from "@/lib/dashboard/snapshot-flag";
 import { prefetchDashboardSnapshot } from "@/lib/queries/use-dashboard-snapshot";
 import { clearOfflineCachesForSessionEnd } from "@/lib/pwa/query-persister";
+import { settleWithin } from "@/lib/async/settle-within";
 import { sanitizeSameOriginPath } from "@/lib/url-safety";
 import { localizedSignInError } from "@/lib/api/localized-error";
 import { formatDate } from "@/lib/format";
@@ -51,6 +52,9 @@ function deletionPendingMessage(t: Translate, purgeAt: unknown): string {
     : t("auth.deletionPendingNoDate");
 }
 
+/** How long the single-sign-on start waits for the offline copies to go. */
+const SSO_CLEANUP_WAIT_MS = 1_500;
+
 /** The message for the `?error=` a sign-in redirect (the SSO callback) set. */
 function signInRedirectError(
   searchParams: URLSearchParams,
@@ -183,8 +187,14 @@ export default function LoginPage() {
       params.set("client_proto", clientTransport.protocol);
       params.set("client_host", clientTransport.host);
     }
-    // The session starts on the way back; the last account's copies go first.
-    await clearOfflineCachesForSessionEnd();
+    // The session starts on the way back; the last account's copies go
+    // first. Bounded: WebKit can leave an IndexedDB open hanging after the
+    // app returns from the background, and the button must still work.
+    await settleWithin(
+      clearOfflineCachesForSessionEnd(),
+      SSO_CLEANUP_WAIT_MS,
+      undefined,
+    );
     loadDocument(`/api/auth/oidc/login?${params}`);
   }
 
diff --git a/src/components/auth/claim-profile.tsx b/src/components/auth/claim-profile.tsx
index 540fa04ea..3ea40d5e6 100644
--- a/src/components/auth/claim-profile.tsx
+++ b/src/components/auth/claim-profile.tsx
@@ -23,12 +23,16 @@ import { showErrorToast } from "@/lib/errors/error-toast";
 import { useFormatters, useTranslations } from "@/lib/i18n/context";
 import { loadDocument } from "@/lib/navigation/load-document";
 import { clearOfflineCachesForSessionEnd } from "@/lib/pwa/query-persister";
+import { settleWithin } from "@/lib/async/settle-within";
 import {
   useClaimProfile,
   useClaimProfileSso,
   useProfileClaimPreview,
 } from "@/lib/queries/use-profile-claim";
 
+/** How long the single-sign-on claim waits for the offline copies to go. */
+const SSO_CLEANUP_WAIT_MS = 1_500;
+
 /**
  * v1.42 (#959) — the person a managed profile describes takes it over as
  * their own account (`/auth/claim?token=hlp_…`).
@@ -111,8 +115,13 @@ export function ClaimProfile({
             next.searchParams.set("client_proto", clientTransport.protocol);
             next.searchParams.set("client_host", clientTransport.host);
           }
-          // The session starts on the way back; the last account's copies go first.
-          await clearOfflineCachesForSessionEnd();
+          // The session starts on the way back; the last account's copies
+          // go first, waited on no longer than on the sign-in page.
+          await settleWithin(
+            clearOfflineCachesForSessionEnd(),
+            SSO_CLEANUP_WAIT_MS,
+            undefined,
+          );
           loadDocument(`${next.pathname}${next.search}`);
         },
       },