diff --git a/addons/website_event_track_online/static/src/js/service_worker.js b/addons/website_event_track_online/static/src/js/service_worker.js
index cde0399cd5a..ac1a8249a15 100644
--- a/addons/website_event_track_online/static/src/js/service_worker.js
+++ b/addons/website_event_track_online/static/src/js/service_worker.js
@@ -151,7 +151,10 @@ const isCachableRequest = (request) => isGET(request) || isCachableURL(request.u
 const matchCache = async (request) => {
     if (isGET(request)) {
         const cache = await caches.open(cacheName);
-        return await cache.match(request);
+        const response = await cache.match(request.url);
+        if (response) {
+            return deserializeResponse(await serializeResponse(response.clone()));
+        }
     }
     if (isCachableURL(request.url)) {
         const serializedRequest = await serializeRequest(request);
@@ -217,6 +220,50 @@ const processPendingRequests = async () => {
     }
 };
 
+/**
+ * Add given urls to the Cache, skipping the ones already present
+ * @param {Array<string>} urls
+ */
+const prefetchUrls = async (urls = []) => {
+    const cache = await caches.open(cacheName);
+    let urlsToCache = new Set(urls);
+    for (let url of urlsToCache) {
+        (await cache.match(url)) ? urlsToCache.delete(url) : undefined;
+    }
+    return cache.addAll([...urlsToCache]);
+};
+
+/**
+ * Handle the message sent to the Worker (using the postMessage() method).
+ * The message is defined by the name of the action to perform and its associated parameters (optional).
+ *
+ * Actions:
+ * - prefetch-pages: add {Array} urls with their "alternative url" to the Cache (if not already present).
+ * - prefetch-assets: add {Array} urls to the Cache (if not already present).
+ *
+ * @param {Object} data
+ * @param {string} data.action action's name
+ * @param {*} data.* action's parameter(s)
+ * @returns {Promise}
+ */
+const processMessage = (data) => {
+    const { action } = data;
+    switch (action) {
+        case "prefetch-pages":
+            const { urls: pagesUrls } = data;
+            // To prevent redirection cached by the browser (cf. 301 Permanently Moved) from breaking the offline cache
+            // we also add alternative urls with the following rule:
+            // * if original url has a trailing "/", adds url with striped trailing "/"
+            // * if original url doesn't end with "/", adds url without the trailing "/"
+            const maybeRedirectedUrl = pagesUrls.map((url) => (url.endsWith("/") ? url.slice(0, -1) : url));
+            return prefetchUrls([...pagesUrls, ...maybeRedirectedUrl]);
+        case "prefetch-assets":
+            const { urls: assetsUrls } = data;
+            return prefetchUrls(assetsUrls);
+    }
+    throw new Error(`Action '${action}' not found.`);
+};
+
 self.addEventListener("fetch", (event) => {
     event.respondWith(processFetchEvent(event));
 });
@@ -227,3 +274,7 @@ self.addEventListener("sync", (event) => {
         event.waitUntil(processPendingRequests());
     }
 });
+
+self.addEventListener("message", (event) => {
+    event.waitUntil(processMessage(event.data));
+});
diff --git a/addons/website_event_track_online/static/src/js/website_event_pwa_widget.js b/addons/website_event_track_online/static/src/js/website_event_pwa_widget.js
index c9bc42a8ccd..77d12e4bb1b 100644
--- a/addons/website_event_track_online/static/src/js/website_event_pwa_widget.js
+++ b/addons/website_event_track_online/static/src/js/website_event_pwa_widget.js
@@ -51,7 +51,7 @@ odoo.define("website_event_track_online.website_event_pwa_widget", function (req
         start: function () {
             var superProm = this._super.apply(this, arguments);
             window.addEventListener("beforeinstallprompt", this.beforeInstallPromptHandler);
-            return superProm.then(this._registerServiceWorker.bind(this));
+            return superProm.then(this._registerServiceWorker.bind(this)).then(this._prefetch.bind(this));
         },
 
         /**
@@ -80,6 +80,15 @@ odoo.define("website_event_track_online.website_event_pwa_widget", function (req
             return "";
         },
 
+        /**
+         * Returns the PWA's scope
+         * @private
+         * @returns {String}
+         */
+        _getScope: function () {
+            return this._getLangPrefix() + "/event";
+        },
+
         /**
          * @private
          */
@@ -88,6 +97,36 @@ odoo.define("website_event_track_online.website_event_pwa_widget", function (req
             $(".o_livechat_button").css("bottom", "0");
         },
 
+        /**
+         * Parse the current page for first-level children pages and ask the ServiceWorker
+         * to already fetch them to populate the cache.
+         * @private
+         */
+        _prefetch: function () {
+            if (!("serviceWorker" in navigator)) {
+                return;
+            }
+            var assetsUrls = Array.from(document.querySelectorAll('link[rel="stylesheet"], script[src]')).map(function (el) {
+                return el.href || el.src;
+            });
+            navigator.serviceWorker.ready.then(function (registration) {
+                registration.active.postMessage({
+                    action: "prefetch-assets",
+                    urls: assetsUrls,
+                });
+            });
+            var currentPageUrl = window.location.href;
+            var childrenPagesUrls = Array.from(document.querySelectorAll('a[href^="' + this._getScope() + '/"]')).map(function (el) {
+                return el.href;
+            });
+            navigator.serviceWorker.ready.then(function (registration) {
+                registration.active.postMessage({
+                    action: "prefetch-pages",
+                    urls: childrenPagesUrls.concat(currentPageUrl),
+                });
+            });
+        },
+
         /**
          *
          * @private
@@ -96,9 +135,9 @@ odoo.define("website_event_track_online.website_event_pwa_widget", function (req
             if (!("serviceWorker" in navigator)) {
                 return;
             }
-            var langPrefix = this._getLangPrefix();
-            navigator.serviceWorker
-                .register(langPrefix + "/event/service-worker.js", { scope: langPrefix + "/event" })
+            var scope = this._getScope();
+            return navigator.serviceWorker
+                .register(scope + "/service-worker.js", { scope: scope })
                 .then(function (registration) {
                     console.info("Registration successful, scope is:", registration.scope);
                 })