diff --git a/web/test-browser-wasm-smoke-opfs-basic-sections.js b/web/test-browser-wasm-smoke-opfs-basic-sections.js
index 1ee4040..26852bf 100644
--- a/web/test-browser-wasm-smoke-opfs-basic-sections.js
+++ b/web/test-browser-wasm-smoke-opfs-basic-sections.js
@@ -125,4 +125,23 @@ export async function runBrowserOpfsBasicSections(context, simulator) {
         "LinuxCNC OPFS program file was not restored across WASM simulator instances");
     });
   });
+
+  await runSection("opfs program restore with independent mount", async () => {
+    await withSmokeSimulator(async (independentMountSimulator) => {
+      // LinuxCNC source basis: rs274ngc_pre.cc open()/read_text()
+      // reads the mirrored program file. A different mount point proves
+      // the program came from OPFS instead of a prior WASM FS mirror.
+      const independentMountEvents = await independentMountSimulator.parseFile(
+        "programs/browser-smoke.ngc",
+        "linuxcnc",
+        { backend: "linuxcnc-rs274" },
+      );
+      expectEvent(independentMountEvents, (event) => event.type === "rapid" && near(event.end.x, 1),
+        "LinuxCNC OPFS program file was not restored through an independent WASM mount");
+      const independentMountPath = independentMountSimulator.fs.opfs.resolvePath("programs/browser-smoke.ngc");
+      if (!independentMountPath.startsWith("/cnc-independent/")) {
+        throw new Error("independent OPFS mount point was not used for restored program parsing");
+      }
+    }, { mountPoint: "/cnc-independent", workspacePath: "cnc-simulator-smoke" });
+  });
 }