diff --git a/addons/web/__manifest__.py b/addons/web/__manifest__.py
index 2c633f76f3d..38643f7bf7b 100644
--- a/addons/web/__manifest__.py
+++ b/addons/web/__manifest__.py
@@ -111,7 +111,6 @@ This module provides the core of the Odoo Web Client.
             'web/static/lib/clipboard/clipboard.js',
             'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/lib/qweb/qweb2.js',
-            'web/static/src/legacy/js/assets.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/content-disposition.js',
@@ -309,7 +308,6 @@ This module provides the core of the Odoo Web Client.
             'web/static/lib/clipboard/clipboard.js',
             'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/lib/qweb/qweb2.js',
-            'web/static/src/legacy/js/assets.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/content-disposition.js',
diff --git a/addons/web/static/src/core/assets.js b/addons/web/static/src/core/assets.js
index e149acdd51c..27aff25c951 100644
--- a/addons/web/static/src/core/assets.js
+++ b/addons/web/static/src/core/assets.js
@@ -69,9 +69,16 @@ export const _loadCSS = (assets.loadCSS = memoize(function loadCSS(url, retryCou
         linkEl.addEventListener("load", () => resolve(true));
         linkEl.addEventListener("error", async () => {
             if (retryCount < assets.retries.count) {
-                await new Promise(resolve => setTimeout(resolve, assets.retries.delay + assets.retries.extraDelay * retryCount));
+                await new Promise((resolve) =>
+                    setTimeout(
+                        resolve,
+                        assets.retries.delay + assets.retries.extraDelay * retryCount
+                    )
+                );
                 linkEl.remove();
-                loadCSS(url, retryCount + 1).then(resolve).catch(reject);
+                loadCSS(url, retryCount + 1)
+                    .then(resolve)
+                    .catch(reject);
             } else {
                 reject(new AssetsLoadingError(`The loading of ${url} failed`));
             }
@@ -105,8 +112,7 @@ export const _loadXML = (assets.loadXML = function loadXML(xml, app = defaultApp
         throw new Error(doc.querySelector("parsererror").textContent.trim());
     }
 
-    for (const element of doc.querySelectorAll("templates > [t-name][owl]")) {
-        element.removeAttribute("owl");
+    for (const element of doc.querySelectorAll("templates > [t-name]")) {
         const name = element.getAttribute("t-name");
         const previous = templates.querySelector(`[t-name="${name}"]`);
         if (previous) {
diff --git a/addons/web/static/src/legacy/js/assets.js b/addons/web/static/src/legacy/js/assets.js
deleted file mode 100644
index 8edc49e1942..00000000000
--- a/addons/web/static/src/legacy/js/assets.js
+++ /dev/null
@@ -1,20 +0,0 @@
-/** @odoo-module **/
-
-import {assets} from "@web/core/assets";
-
-const loadXML = assets.loadXML;
-assets.loadXML = function (xml, app) {
-    loadXML(xml, app);
-
-    const doc = new DOMParser().parseFromString(xml, "text/xml");
-    const qwebTemplates = document.createElement("templates");
-    for (const element of doc.querySelectorAll("templates > [t-name]:not([owl]), templates > [t-extend]:not([owl])")) {
-        qwebTemplates.appendChild(element);
-    }
-
-    // don't use require to apply the patch before the first template loading.
-    odoo.ready('@web/legacy/js/services/core').then(function () {
-        const { qweb } = odoo.__DEBUG__.services['@web/legacy/js/services/core'];
-        qweb.add_template(qwebTemplates);
-    });
-}
diff --git a/addons/website_slides/__manifest__.py b/addons/website_slides/__manifest__.py
index 7ea5fc07717..68f40322122 100644
--- a/addons/website_slides/__manifest__.py
+++ b/addons/website_slides/__manifest__.py
@@ -192,7 +192,6 @@ Featuring
             'web/static/lib/clipboard/clipboard.js',
             'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/lib/qweb/qweb2.js',
-            'web/static/src/legacy/js/assets.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/content-disposition.js',