diff --git a/addons/im_livechat/__manifest__.py b/addons/im_livechat/__manifest__.py
index 8966d6788bb..be340ea9000 100644
--- a/addons/im_livechat/__manifest__.py
+++ b/addons/im_livechat/__manifest__.py
@@ -92,6 +92,7 @@ Help your customers with this chat, and analyse their feedback.
         'im_livechat.assets_embed_core': [
             'web/static/lib/odoo_ui_icons/style.css',
             'web/static/src/scss/ui.scss',
+            ('remove', 'web/static/src/core/browser/title_service.js'),
             'mail/static/src/core/common/**/*',
             'mail/static/src/discuss/core/common/*',
             'mail/static/src/discuss/call/common/**',
diff --git a/addons/mail/static/src/core/common/out_of_focus_service.js b/addons/mail/static/src/core/common/out_of_focus_service.js
index 40c57623ea1..66780ff1b44 100644
--- a/addons/mail/static/src/core/common/out_of_focus_service.js
+++ b/addons/mail/static/src/core/common/out_of_focus_service.js
@@ -18,16 +18,14 @@ export class OutOfFocusService {
      * @param {Partial<import("services").Services>} services
      */
     constructor(env, services) {
+        this.setup(env, services);
+    }
+
+    setup(env, services) {
         this.env = env;
         this.audio = undefined;
-        this.counter = 0;
         this.multiTab = services.multi_tab;
         this.notificationService = services.notification;
-        this.titleService = services.title;
-        env.bus.addEventListener("window_focus", () => {
-            this.counter = 0;
-            this.titleService.setParts({ _chat: undefined });
-        });
     }
 
     async notify(message, channel) {
@@ -61,10 +59,6 @@ export class OutOfFocusService {
             title: notificationTitle,
             type: "info",
         });
-        this.counter++;
-        this.titleService.setParts({
-            _chat: this.counter === 1 ? _t("1 Message") : _t("%s Messages", this.counter),
-        });
     }
 
     async hasServiceWorkInstalledAndPushSubscriptionActive() {
@@ -165,7 +159,7 @@ export class OutOfFocusService {
 }
 
 export const outOfFocusService = {
-    dependencies: ["multi_tab", "notification", "title"],
+    dependencies: ["multi_tab", "notification"],
     /**
      * @param {import("@web/env").OdooEnv} env
      * @param {Partial<import("services").Services>} services
diff --git a/addons/mail/static/src/core/web/out_of_focus_service_patch.js b/addons/mail/static/src/core/web/out_of_focus_service_patch.js
new file mode 100644
index 00000000000..d38b1ecc541
--- /dev/null
+++ b/addons/mail/static/src/core/web/out_of_focus_service_patch.js
@@ -0,0 +1,25 @@
+/* @odoo-module */
+
+import { OutOfFocusService, outOfFocusService } from "@mail/core/common/out_of_focus_service";
+import { patch } from "@web/core/utils/patch";
+import { _t } from "@web/core/l10n/translation";
+import { sprintf } from "@web/core/utils/strings";
+
+patch(OutOfFocusService.prototype, {
+    setup(env, services) {
+        super.setup(env, services);
+        this.titleService = services.title;
+        this.counter = 0;
+        env.bus.addEventListener("window_focus", () => {
+            this.counter = 0;
+            this.titleService.setParts({ _chat: undefined });
+        });
+    },
+    notify() {
+        super.notify(...arguments);
+        this.counter++;
+        const titlePattern = this.counter === 1 ? _t("%s Message") : _t("%s Messages");
+        this.titleService.setParts({ _chat: sprintf(titlePattern, this.counter) });
+    },
+});
+outOfFocusService.dependencies = [...outOfFocusService.dependencies, "title"];