diff --git a/packages/app-bundle/overlay/packages/app/src/components/settings-v2/developer-tools-controller.ts b/packages/app-bundle/overlay/packages/app/src/components/settings-v2/developer-tools-controller.ts
index 9813b8c4..12a6e867 100644
--- a/packages/app-bundle/overlay/packages/app/src/components/settings-v2/developer-tools-controller.ts
+++ b/packages/app-bundle/overlay/packages/app/src/components/settings-v2/developer-tools-controller.ts
@@ -161,20 +161,14 @@ export function createDeveloperToolsController() {
           settings.developer.setAmicodePath(DEFAULT_AMICODE_PATH)
         }
       }
-      // Don't persist enabled=false — the marketplace build doesn't render
-      // Developer Tools at all, and persisting false prevents the dev build
-      // from showing it after a bash-script bootstrap without toggle interaction.
+      settings.developer.setEnabled(value)
       if (value) {
-        settings.developer.setEnabled(value)
         // Toggle ON: trigger a full rebuild (shows "Rebuilding..." status)
         rebuild("local")
       } else {
-        // Toggle OFF: show switching status, then the extension restores + reloads.
-        // Don't persist false — the reload brings up the marketplace build which
-        // doesn't have this section anyway.
+        // Toggle OFF: restore marketplace build and reload.
         setRebuildState("rebuilding")
         setRebuildError(undefined)
-        // Send enabled=false explicitly (can't rely on the signal since we didn't persist it)
         if (!inAmicode()) return
         setPending(true)
         setStatus(undefined)
diff --git a/packages/app-bundle/overlay/packages/app/src/context/settings.tsx b/packages/app-bundle/overlay/packages/app/src/context/settings.tsx
index 25fb8be8..299cbc27 100644
--- a/packages/app-bundle/overlay/packages/app/src/context/settings.tsx
+++ b/packages/app-bundle/overlay/packages/app/src/context/settings.tsx
@@ -216,7 +216,7 @@ const defaultSettings: Settings = {
     configDir: "",
   },
   developer: {
-    enabled: true,
+    enabled: false,
     opencodePath: "",
     amicodePath: "",
   },
diff --git a/packages/extension/.gitignore b/packages/extension/.gitignore
index b3fe3184..ac059ade 100644
--- a/packages/extension/.gitignore
+++ b/packages/extension/.gitignore
@@ -2,3 +2,4 @@ dev/brand_harness/main.js
 dev/pulseplot_harness/main.js
 scripts/benchmark/out/
 scripts/benchmark/traces/
+dist.marketplace-backup/
diff --git a/packages/extension/src/chat_bridge.ts b/packages/extension/src/chat_bridge.ts
index d1469af7..fe3b1756 100644
--- a/packages/extension/src/chat_bridge.ts
+++ b/packages/extension/src/chat_bridge.ts
@@ -258,34 +258,40 @@ export function handleAmicodeBridgeMessage(msg: unknown, io: BridgeIo): boolean
     };
 
     if (!enabled) {
-      // Toggle OFF: clear overrides, restore marketplace extension, and reload.
+      // Toggle OFF: clear overrides, reinstall the marketplace extension, and reload.
       void vscode.workspace.getConfiguration("amicode").update("opencodeBinary", "", vscode.ConfigurationTarget.Global);
       void vscode.workspace.getConfiguration("amicode").update("devAssetRoot", "", vscode.ConfigurationTarget.Global);
 
-      // Restore the marketplace extension dist if a backup exists
+      // Guard: write a temporary marker so onboarding won't re-trigger after
+      // the reinstall. The marker is consumed (deleted) on next activation.
+      // A manual uninstall by the user does NOT write this marker, so
+      // onboarding correctly re-triggers for genuine fresh installs.
+      try {
+        const { writeDevtoolsRestoreMarker } = require("./substrate/vault_store") as typeof import("./substrate/vault_store");
+        writeDevtoolsRestoreMarker();
+      } catch { /* non-critical — worst case onboarding re-shows */ }
+
+      // Reinstall from the marketplace to restore the user's current release.
+      // The old backup approach was fragile (went stale on extension updates).
+      // Uninstall+install is the only reliable way to restore a clean dist —
+      // `--force` alone says "already installed" for the same version.
       const installedExt = vscode.extensions.getExtension("harmoniqs.amicode");
       if (installedExt) {
-        const backupDist = path.join(installedExt.extensionPath, "dist.marketplace-backup");
-        const installedDist = path.join(installedExt.extensionPath, "dist");
-        if (fs.existsSync(backupDist)) {
-          try {
-            const backupFiles = fs.readdirSync(backupDist).filter(f => f.endsWith(".js") || f.endsWith(".js.map"));
-            for (const f of backupFiles) {
-              fs.copyFileSync(path.join(backupDist, f), path.join(installedDist, f));
-            }
-            console.log("[amicode/bridge] restored marketplace dist from backup");
-          } catch (restoreErr) {
-            console.warn("[amicode/bridge] marketplace dist restore failed:", restoreErr);
+        const { exec } = require("child_process") as typeof import("child_process");
+        const extId = "harmoniqs.amicode";
+        exec(`code --uninstall-extension ${extId} && code --install-extension ${extId}`, { timeout: 60_000 }, (err) => {
+          if (err) {
+            console.warn("[amicode/bridge] marketplace reinstall failed:", err.message);
+          } else {
+            console.log("[amicode/bridge] reinstalled marketplace extension");
           }
-        }
+          void vscode.commands.executeCommand("workbench.action.reloadWindow");
+        });
+      } else {
+        void vscode.commands.executeCommand("workbench.action.reloadWindow");
       }
 
-      // Don't restart server separately — reloading the window does it.
-      // Don't send reloadNeeded — the auto-reload handles it silently.
       io.postToWebview(reply);
-      setTimeout(() => {
-        void vscode.commands.executeCommand("workbench.action.reloadWindow");
-      }, 300);
       return true;
     }
 
diff --git a/packages/extension/src/opencode_config.ts b/packages/extension/src/opencode_config.ts
index 8a111445..eb6b973f 100644
--- a/packages/extension/src/opencode_config.ts
+++ b/packages/extension/src/opencode_config.ts
@@ -26,6 +26,7 @@ import {
   readMemoryIndexLines,
   hasOnboardingCompleted,
   onboardingDir,
+  consumeDevtoolsRestoreMarker,
 } from "./substrate/vault_store";
 import { resolveMountStack, personalMount, type Mount, type MountStack } from "./substrate/mount_store";
 import {
@@ -614,6 +615,7 @@ export function prepareOpencodeProject(opts: OpencodeConfigOptions): OpencodePro
       vaultDir !== "" &&
       readProfileMd(vaultDir) === "" &&
       !hasOnboardingCompleted(onboardingDir()) &&
+      !consumeDevtoolsRestoreMarker() &&
       !profileHasIdentity(); // the welcome WIZARD already collected identity — don't re-interview
     if (shouldOnboard && overture && score0) {
       // Chained: ONE compiled section, ONE manifest (id `overture`, stages =
diff --git a/packages/extension/src/substrate/vault_store.ts b/packages/extension/src/substrate/vault_store.ts
index a9a02ef2..8e64aaab 100644
--- a/packages/extension/src/substrate/vault_store.ts
+++ b/packages/extension/src/substrate/vault_store.ts
@@ -107,3 +107,28 @@ export function hasOnboardingCompleted(onboardingStreamDir: string): boolean {
   }
   return false;
 }
+
+// ─── Devtools restore marker ─────────────────────────────────────────────────
+// A temporary file that tells the next activation "this reinstall was triggered
+// by the devtools toggle, not a manual user action — skip onboarding." The
+// marker is consumed (deleted) on read so it only suppresses once.
+
+const DEVTOOLS_RESTORE_MARKER = ".devtools-restore";
+
+/** Write the devtools restore marker. Called by toggle-OFF before uninstall. */
+export function writeDevtoolsRestoreMarker(opsDir: string = amicodeOpsDir()): void {
+  fs.mkdirSync(opsDir, { recursive: true });
+  fs.writeFileSync(path.join(opsDir, DEVTOOLS_RESTORE_MARKER), String(Date.now()));
+}
+
+/** Check and consume the devtools restore marker. Returns true if it existed
+ *  (meaning this activation follows a toggle-OFF reinstall, not a fresh install). */
+export function consumeDevtoolsRestoreMarker(opsDir: string = amicodeOpsDir()): boolean {
+  const markerPath = path.join(opsDir, DEVTOOLS_RESTORE_MARKER);
+  try {
+    fs.unlinkSync(markerPath);
+    return true;
+  } catch {
+    return false;
+  }
+}
diff --git a/packages/extension/test/onboarding_routing.test.ts b/packages/extension/test/onboarding_routing.test.ts
index 46b070e0..ed400d2f 100644
--- a/packages/extension/test/onboarding_routing.test.ts
+++ b/packages/extension/test/onboarding_routing.test.ts
@@ -19,6 +19,12 @@ import {
   writeWelcomeShown,
 } from "../src/onboarding_routing";
 
+import {
+  hasOnboardingCompleted,
+  writeDevtoolsRestoreMarker,
+  consumeDevtoolsRestoreMarker,
+} from "../src/substrate/vault_store";
+
 // ─── AC10: Routing predicate (pure function, table-driven) ───────────────────
 
 describe("resolveOnboardingAction — routing predicate (AC10)", () => {
@@ -237,3 +243,36 @@ describe("welcome_shown flag semantics (AC6)", () => {
     expect(readWelcomeShown(file)).toBe(true);
   });
 });
+
+// ─── devtools restore marker — toggle-OFF guard ─────────────────────────────
+
+describe("devtools restore marker — toggle-OFF guard", () => {
+  let tmpDir: string;
+
+  beforeEach(() => {
+    tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), "devtools-marker-"));
+  });
+  afterEach(() => {
+    fs.rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  it("consumeDevtoolsRestoreMarker returns false when no marker exists", () => {
+    expect(consumeDevtoolsRestoreMarker(tmpDir)).toBe(false);
+  });
+
+  it("writeDevtoolsRestoreMarker + consumeDevtoolsRestoreMarker returns true and deletes the marker", () => {
+    writeDevtoolsRestoreMarker(tmpDir);
+    expect(consumeDevtoolsRestoreMarker(tmpDir)).toBe(true);
+    // Second consume returns false (marker was deleted)
+    expect(consumeDevtoolsRestoreMarker(tmpDir)).toBe(false);
+  });
+
+  it("does not interfere with onboarding completion state", () => {
+    // Marker exists but onboarding events.jsonl does not
+    writeDevtoolsRestoreMarker(tmpDir);
+    expect(hasOnboardingCompleted(tmpDir)).toBe(false);
+    // Consuming the marker doesn't create onboarding_completed
+    consumeDevtoolsRestoreMarker(tmpDir);
+    expect(hasOnboardingCompleted(tmpDir)).toBe(false);
+  });
+});