diff --git a/addons/mail/static/src/components/messaging_menu/messaging_menu.js b/addons/mail/static/src/components/messaging_menu/messaging_menu.js
index 36859ccb62b..5250ecccba9 100644
--- a/addons/mail/static/src/components/messaging_menu/messaging_menu.js
+++ b/addons/mail/static/src/components/messaging_menu/messaging_menu.js
@@ -45,13 +45,6 @@ export class MessagingMenu extends Component {
         return this.messaging && this.messaging.models['MessagingMenu'].get(this.props.localId);
     }
 
-    /**
-     * @returns {string}
-     */
-    get mobileNewMessageInputPlaceholder() {
-        return this.env._t("Search user...");
-    }
-
     //--------------------------------------------------------------------------
     // Handlers
     //--------------------------------------------------------------------------
diff --git a/addons/mail/static/src/components/messaging_menu/messaging_menu.xml b/addons/mail/static/src/components/messaging_menu/messaging_menu.xml
index be110a8881d..1d5f911fc9b 100644
--- a/addons/mail/static/src/components/messaging_menu/messaging_menu.xml
+++ b/addons/mail/static/src/components/messaging_menu/messaging_menu.xml
@@ -42,7 +42,7 @@
                                     className="'o_MessagingMenu_mobileNewMessageInput'"
                                     customClass="id + '_mobileNewMessageInputAutocomplete'"
                                     isFocusOnMount="true"
-                                    placeholder="mobileNewMessageInputPlaceholder"
+                                    placeholder="messagingMenu.mobileNewMessageInputPlaceholder"
                                     select="_onMobileNewMessageInputSelect"
                                     source="_onMobileNewMessageInputSource"
                                     onHide="_onHideMobileNewMessage"
diff --git a/addons/mail/static/src/models/messaging_menu.js b/addons/mail/static/src/models/messaging_menu.js
index f2cd3717b0a..3be53d327df 100644
--- a/addons/mail/static/src/models/messaging_menu.js
+++ b/addons/mail/static/src/models/messaging_menu.js
@@ -59,6 +59,13 @@ registerModel({
             }
             return clear();
         },
+        /**
+         * @private
+         * @returns {string}
+         */
+        _computeMobileNewMessageInputPlaceholder() {
+            return this.env._t("Search user...");
+        },
         /**
          * @returns {FieldCommand}
          */
@@ -107,6 +114,9 @@ registerModel({
             inverse: 'messagingMenu',
             isCausal: true,
         }),
+        mobileNewMessageInputPlaceholder: attr({
+            compute: '_computeMobileNewMessageInputPlaceholder',
+        }),
         /**
          * States all the pinned channels that have unread messages.
          */