From 9b0c26846aa1f39cfc30da86593e4454df321023 Mon Sep 17 00:00:00 2001
From: r-zakarya <82443831+r-zakarya@users.noreply.github.com>
Date: Thu, 9 Jul 2026 22:59:07 +0100
Subject: [PATCH] fix(sync): guard the Sync-now button against concurrent runs
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Clicking Sync twice started a second concurrent runSyncNow, and the click
event was passed as runSyncNow's `_attempt` retry counter (so the "Syncing…"
toast and 412-retry bound were both broken). Wrapped the handler: disable the
button while a sync runs, and call runSyncNow() with no arg. Internal retries
are unaffected.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---
 js/app.js | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/js/app.js b/js/app.js
index 60c1695..642a48c 100644
--- a/js/app.js
+++ b/js/app.js
@@ -8938,7 +8938,15 @@ async function init() {
         Bridge.setPref(SYNC_PREFS.preBackup, e.target.checked ? '1' : ''));
     if (syncSetPwd) syncSetPwd.addEventListener('click', syncSetEncPwdFlow);
     if (syncTest)   syncTest.addEventListener('click', syncTestConnection);
-    if (syncNow)    syncNow.addEventListener('click', runSyncNow);
+    // Guard the user entry point: ignore clicks while a sync is running (no
+    // concurrent syncs) and call runSyncNow() with NO arg — the click event
+    // must not land in its `_attempt` retry counter. Internal retries call
+    // runSyncNow directly, so they're unaffected.
+    if (syncNow) syncNow.addEventListener('click', async () => {
+        if (syncNow.disabled) return;
+        syncNow.disabled = true;
+        try { await runSyncNow(); } finally { syncNow.disabled = false; }
+    });
 
     $('#settingAutoBackupEnabled').addEventListener('change', onToggleAutoBackup);
     $('#autoBackupPickDirBtn').addEventListener('click', pickAutoBackupFolder);