diff --git a/addons/mrp_subcontracting/__manifest__.py b/addons/mrp_subcontracting/__manifest__.py
index 42d89893290..9226c924f36 100644
--- a/addons/mrp_subcontracting/__manifest__.py
+++ b/addons/mrp_subcontracting/__manifest__.py
@@ -87,11 +87,9 @@
             'web/static/lib/bootstrap/js/dist/toast.js',
             'web/static/lib/select2/select2.js',
             'web/static/lib/clipboard/clipboard.js',
-            'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/jquery.js',
-            'web/static/src/legacy/js/libs/jSignatureCustom.js',
             'web/static/src/legacy/js/core/bus.js',
             'web/static/src/legacy/js/core/class.js',
             'web/static/src/legacy/js/core/dialog.js',
diff --git a/addons/project/__manifest__.py b/addons/project/__manifest__.py
index 88632e58811..aa37bcfd017 100644
--- a/addons/project/__manifest__.py
+++ b/addons/project/__manifest__.py
@@ -137,11 +137,9 @@
             'web/static/lib/bootstrap/js/dist/toast.js',
             'web/static/lib/select2/select2.js',
             'web/static/lib/clipboard/clipboard.js',
-            'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/jquery.js',
-            'web/static/src/legacy/js/libs/jSignatureCustom.js',
             'web/static/src/legacy/js/core/bus.js',
             'web/static/src/legacy/js/core/class.js',
             'web/static/src/legacy/js/core/dialog.js',
diff --git a/addons/web/__manifest__.py b/addons/web/__manifest__.py
index b155151ce7e..d1d3bdd3a87 100644
--- a/addons/web/__manifest__.py
+++ b/addons/web/__manifest__.py
@@ -89,11 +89,9 @@ This module provides the core of the Odoo Web Client.
             'web/static/lib/bootstrap/js/dist/toast.js',
             'web/static/lib/select2/select2.js',
             'web/static/lib/clipboard/clipboard.js',
-            'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/jquery.js',
-            'web/static/src/legacy/js/libs/jSignatureCustom.js',
             'web/static/src/legacy/js/core/bus.js',
             'web/static/src/legacy/js/core/class.js',
             'web/static/src/legacy/js/core/dialog.js',
@@ -217,11 +215,9 @@ This module provides the core of the Odoo Web Client.
             'web/static/lib/bootstrap/js/dist/toast.js',
             'web/static/lib/select2/select2.js',
             'web/static/lib/clipboard/clipboard.js',
-            'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/jquery.js',
-            'web/static/src/legacy/js/libs/jSignatureCustom.js',
             'web/static/src/legacy/js/core/bus.js',
             'web/static/src/legacy/js/core/class.js',
             'web/static/src/legacy/js/core/dialog.js',
@@ -455,8 +451,9 @@ This module provides the core of the Odoo Web Client.
             'web/static/lib/stacktracejs/stacktrace.js',
             'web/static/lib/Chart/Chart.js',
             'web/static/lib/chartjs-adapter-luxon/chartjs-adapter-luxon.js',
+            'web/static/lib/jSignature/jSignatureCustom.js',
+            'web/static/src/libs/jSignatureCustom.js',
 
-            # 'web/static/tests/legacy/main_tests.js',
             'web/static/tests/helpers/**/*.js',
             'web/static/tests/views/helpers.js',
             'web/static/tests/search/helpers.js',
diff --git a/addons/web/static/src/core/signature/name_and_signature.js b/addons/web/static/src/core/signature/name_and_signature.js
index ac7dad6f4c0..9c600ef336d 100644
--- a/addons/web/static/src/core/signature/name_and_signature.js
+++ b/addons/web/static/src/core/signature/name_and_signature.js
@@ -1,5 +1,6 @@
 /** @odoo-module **/
 
+import { loadJS } from "@web/core/assets";
 import { isMobileOS } from "@web/core/browser/feature_detection";
 import { Dropdown } from "@web/core/dropdown/dropdown";
 import { DropdownItem } from "@web/core/dropdown/dropdown_item";
@@ -43,6 +44,11 @@ export class NameAndSignature extends Component {
             this.fonts = await this.rpc(`/web/sign/get_fonts/${this.props.defaultFont}`);
         });
 
+        onWillStart(async () => {
+            await loadJS("/web/static/lib/jSignature/jSignatureCustom.js");
+            await loadJS("/web/static/src/libs/jSignatureCustom.js");
+        });
+
         this.signatureRef = useRef("signature");
         useEffect(
             (el) => {
diff --git a/addons/web/static/src/legacy/js/libs/jSignatureCustom.js b/addons/web/static/src/libs/jSignatureCustom.js
similarity index 100%
rename from addons/web/static/src/legacy/js/libs/jSignatureCustom.js
rename to addons/web/static/src/libs/jSignatureCustom.js
diff --git a/addons/web/static/tests/setup.js b/addons/web/static/tests/setup.js
index f0c07fd4986..ad35feeae7c 100644
--- a/addons/web/static/tests/setup.js
+++ b/addons/web/static/tests/setup.js
@@ -3,7 +3,7 @@
 import LegacyBus from "@web/legacy/js/core/bus";
 import { assets, templates } from "@web/core/assets";
 import { browser, makeRAMLocalStorage } from "@web/core/browser/browser";
-import { nextTick, patchTimeZone, patchWithCleanup } from "@web/../tests/helpers/utils";
+import { patchTimeZone, patchWithCleanup } from "@web/../tests/helpers/utils";
 import { memoize } from "@web/core/utils/functions";
 import { registerCleanup } from "./helpers/cleanup";
 import { prepareRegistriesWithCleanup } from "./helpers/mock_env";
@@ -298,7 +298,7 @@ function patchAssets() {
                     "%c[assets] fetch (mock) JS ressource: " + ressource,
                     "color: #66e; font-weight: bold;"
                 );
-                return nextTick();
+                return Promise.resolve();
             }
             console.log(
                 "%c[assets] fetch JS ressource: " + ressource,
@@ -312,7 +312,7 @@ function patchAssets() {
                     "%c[assets] fetch (mock) CSS ressource: " + ressource,
                     "color: #66e; font-weight: bold;"
                 );
-                return nextTick();
+                return Promise.resolve();
             }
             console.log(
                 "%c[assets] fetch CSS ressource: " + ressource,
diff --git a/addons/web_editor/__manifest__.py b/addons/web_editor/__manifest__.py
index a03356bf2bc..c8230c63470 100644
--- a/addons/web_editor/__manifest__.py
+++ b/addons/web_editor/__manifest__.py
@@ -76,11 +76,9 @@ Odoo Web Editor widget.
             'web/static/lib/bootstrap/js/dist/toast.js',
             'web/static/lib/select2/select2.js',
             'web/static/lib/clipboard/clipboard.js',
-            'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/jquery.js',
-            'web/static/src/legacy/js/libs/jSignatureCustom.js',
             'web/static/src/legacy/js/core/bus.js',
             'web/static/src/legacy/js/core/class.js',
             'web/static/src/legacy/js/core/dialog.js',
diff --git a/addons/website_slides/__manifest__.py b/addons/website_slides/__manifest__.py
index 901b14443a3..82f331c7655 100644
--- a/addons/website_slides/__manifest__.py
+++ b/addons/website_slides/__manifest__.py
@@ -176,12 +176,10 @@ Featuring
             'web/static/lib/bootstrap/js/dist/toast.js',
             'web/static/lib/select2/select2.js',
             'web/static/lib/clipboard/clipboard.js',
-            'web/static/lib/jSignature/jSignatureCustom.js',
             'web/static/src/legacy/js/libs/autocomplete.js',
             'web/static/src/legacy/js/libs/bootstrap.js',
             'web/static/src/legacy/js/libs/jquery.js',
             'website/static/src/libs/zoomodoo/zoomodoo.js',
-            'web/static/src/legacy/js/libs/jSignatureCustom.js',
             'web/static/src/legacy/js/core/bus.js',
             'web/static/src/legacy/js/core/class.js',
             'web/static/src/legacy/js/core/dialog.js',