From d8f6be7b1e367644452da2e885b587180b9cd08d Mon Sep 17 00:00:00 2001
From: Linus Rath <139418639+rathlinus@users.noreply.github.com>
Date: Sun, 1 Nov 2026 05:42:00 +0100
Subject: [PATCH] fix: delete a finished export's file from the browser when
 its account signs out

---
 .../__tests__/mail-export-dialog.test.tsx     | 21 +++++++++++++++++++
 .../mail-transfer/mail-transfer-host.tsx      |  7 +++++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/components/mail-transfer/__tests__/mail-export-dialog.test.tsx b/components/mail-transfer/__tests__/mail-export-dialog.test.tsx
index ec0175d28..2b0c24149 100644
--- a/components/mail-transfer/__tests__/mail-export-dialog.test.tsx
+++ b/components/mail-transfer/__tests__/mail-export-dialog.test.tsx
@@ -83,6 +83,27 @@ describe('MailExportDialog', () => {
     expect(useMailTransferStore.getState().request).toBeNull();
   });
 
+  it('signing out stops a running export, or frees a finished one\'s file', async () => {
+    const { runBeforeSignOut } = await import('@/lib/sign-out-cleanup');
+    const controller = new AbortController();
+    render(<MailTransferHost />);
+    act(() => {
+      openMailExport({ mailboxId: 'inbox' });
+      useMailTransferStore.getState().startJob({ kind: 'export', controller, progress: { phase: 'running', exported: 1, failed: 0, failures: [], total: 4, fraction: 0.25 } });
+    });
+    await act(() => runBeforeSignOut('acc1'));
+    expect(controller.signal.aborted).toBe(true);
+
+    const discard = vi.fn(async () => {});
+    act(() => {
+      useMailTransferStore.setState({ request: null, visible: false, job: null });
+      openMailExport({ mailboxId: 'inbox' });
+      useMailTransferStore.getState().startJob({ kind: 'export', controller: new AbortController(), progress: { phase: 'done', exported: 3, failed: 0, failures: [], total: 3, fraction: 1, file: { name: 'a.mbox', size: 1, discard } } });
+    });
+    await act(() => runBeforeSignOut('acc1'));
+    expect(discard).toHaveBeenCalled();
+  });
+
   it('runs on in the background and the chip names the export', () => {
     const controller = new AbortController();
     render(<MailTransferHost />);
diff --git a/components/mail-transfer/mail-transfer-host.tsx b/components/mail-transfer/mail-transfer-host.tsx
index ee8e85174..a69c920e5 100644
--- a/components/mail-transfer/mail-transfer-host.tsx
+++ b/components/mail-transfer/mail-transfer-host.tsx
@@ -20,9 +20,12 @@ export function MailTransferHost() {
   const visible = useMailTransferStore((s) => s.visible);
   const job = useMailTransferStore((s) => s.job);
 
-  // An account that signs out takes its running job and its checkpoints with it.
+  // An account that signs out takes its running job, a finished export's
+  // file in the browser's private storage, and its checkpoints with it.
   useEffect(() => onBeforeSignOut(async (accountId) => {
-    useMailTransferStore.getState().cancelJob();
+    const store = useMailTransferStore.getState();
+    if (isJobActive(store.job)) store.cancelJob();
+    else store.close();
     if (accountId !== "all") await clearCheckpointsFor(accountId);
   }), []);