diff --git a/app/legacy/store.js b/app/legacy/store.js
index 234f95bb..f02cb2f6 100644
--- a/app/legacy/store.js
+++ b/app/legacy/store.js
@@ -969,6 +969,17 @@
   }
 
   async function commit(opts = {}) {
+    // Every mutating path in this module funnels through here before it can
+    // reach a real network write -- scheduleSave()'s own setTimeout calls
+    // this closure-scoped function directly, so patching Store.commit (or
+    // any individual caller) from outside cannot stop it. The tour's own
+    // welcome copy promises "nothing here touches your real files," and
+    // enumerating every caller in tour.js's blocklist misses ones reachable
+    // outside a click (keyboard shortcuts bypass the tour's click-blocking
+    // backdrop entirely, since CSS pointer-events does nothing to keydown
+    // listeners) -- so the guard belongs here, once, covering every path by
+    // construction instead of by an ever-growing enumeration.
+    if (window.__FUNPACK_TOUR__) return;
     if (!state.project) return;
     if (_commitPromise) { _commitQueued = true; return _commitPromise; }
     const skipPreviewRefresh = !!opts.skipPreviewRefresh;