diff --git a/app/docs.test.ts b/app/docs.test.ts
index ddc5179b..cc48add1 100644
--- a/app/docs.test.ts
+++ b/app/docs.test.ts
@@ -135,7 +135,11 @@ test("site includes core guides and production configuration", () => {
   expect(config).toContain(
     '"style-src": ["\'self\'", "\'unsafe-inline\'", "https://fonts.googleapis.com"]',
   );
-  expect(config).toContain('cacheName: "wrnexus-pwa-v2"');
+  expect(config).toContain('cacheName: "wrnexus-pwa-v3"');
+  expect(config).toContain("head: '<script src=\"/pwa-recover.js\" defer></script>'");
+  const recovery = readFileSync(join(root, "public", "pwa-recover.js"), "utf8");
+  expect(recovery).toContain('updateViaCache: "none"');
+  expect(recovery).toContain("registration.update()");
   expect(config).toContain('pattern: "^https://wrnexusjs\\\\.dev/"');
 });
 
diff --git a/public/pwa-recover.js b/public/pwa-recover.js
new file mode 100644
index 00000000..fc9283e3
--- /dev/null
+++ b/public/pwa-recover.js
@@ -0,0 +1,37 @@
+/* global location, navigator, sessionStorage, window */
+(function () {
+  if (!("serviceWorker" in navigator)) return;
+
+  var version = "docs-v3";
+  var workerUrl = "/sw.js?v=" + encodeURIComponent(version);
+  if (window.trustedTypes) {
+    try {
+      workerUrl = window.trustedTypes
+        .createPolicy("wrnexus-pwa-recovery", {
+          createScriptURL: function (value) {
+            return value;
+          },
+        })
+        .createScriptURL(workerUrl);
+    } catch {
+      // A previously-created policy can make creation fail; the same-origin
+      // string remains valid when Trusted Types enforcement is not active.
+    }
+  }
+
+  var reloading = false;
+  navigator.serviceWorker.addEventListener("controllerchange", function () {
+    var key = "wrnexus-pwa-controller-" + version;
+    if (reloading || sessionStorage.getItem(key)) return;
+    reloading = true;
+    sessionStorage.setItem(key, "1");
+    location.reload();
+  });
+
+  navigator.serviceWorker
+    .register(workerUrl, { updateViaCache: "none" })
+    .then(function (registration) {
+      return registration.update();
+    })
+    .catch(function () {});
+})();
diff --git a/wrnexus.config.ts b/wrnexus.config.ts
index 040d25d9..6441c442 100644
--- a/wrnexus.config.ts
+++ b/wrnexus.config.ts
@@ -1,6 +1,9 @@
 import type { AppConfig } from "@wrnexus/styles";
 
 const config: AppConfig = {
+  // Repair clients that are still controlled by an older cached service worker.
+  // This can be removed after every preview client has advanced beyond v3.
+  head: '<script src="/pwa-recover.js" defer></script>',
   mobile: {
     enabled: true,
     appId: "com.example.wrnexusjs",
@@ -15,7 +18,7 @@ const config: AppConfig = {
   pwa: {
     name: "WRNexusJS Documentation",
     shortName: "WRNexusJS Docs",
-    cacheName: "wrnexus-pwa-v2",
+    cacheName: "wrnexus-pwa-v3",
     runtimeCaching: [
       {
         pattern: "^https://wrnexusjs\\.dev/",