diff --git a/addons/portal/static/src/js/portal_chatter.js b/addons/portal/static/src/js/portal_chatter.js
index c80a5f0de97..0f379460d06 100644
--- a/addons/portal/static/src/js/portal_chatter.js
+++ b/addons/portal/static/src/js/portal_chatter.js
@@ -34,27 +34,7 @@ var PortalChatter = publicWidget.Widget.extend({
         this.options = {};
         this._super.apply(this, arguments);
 
-        // underscorize the camelcased option keys
-        _.each(options, function (val, key) {
-            self.options[_.str.underscored(key)] = val;
-        });
-        // set default options
-        this.options = _.defaults(this.options, {
-            'allow_composer': true,
-            'display_composer': false,
-            'csrf_token': odoo.csrf_token,
-            'message_count': 0,
-            'pager_step': 10,
-            'pager_scope': 5,
-            'pager_start': 1,
-            'is_user_public': true,
-            'is_user_employee': false,
-            'is_user_publisher': false,
-            'hash': false,
-            'pid': false,
-            'domain': [],
-            'two_columns': false,
-        });
+        this._setOptions(options);
 
         this.set('messages', []);
         this.set('message_count', this.options['message_count']);
@@ -135,6 +115,38 @@ var PortalChatter = publicWidget.Widget.extend({
     // Private
     //--------------------------------------------------------------------------
 
+    /**
+     * Set options
+     *
+     * @param {Array<string>} options: new options to set
+     */
+    _setOptions: function (options) {
+        // underscorize the camelcased option keys
+        const defaultOptions = {
+            'allow_composer': true,
+            'display_composer': false,
+            'csrf_token': odoo.csrf_token,
+            'message_count': 0,
+            'pager_step': 10,
+            'pager_scope': 5,
+            'pager_start': 1,
+            'is_user_public': true,
+            'is_user_employee': false,
+            'is_user_publisher': false,
+            'hash': false,
+            'pid': false,
+            'domain': [],
+            'two_columns': false,
+        };
+
+        this.options = Object.entries(options).reduce(
+            (acc, [key, value]) => {
+                acc[_.str.underscored(key)] = value;
+                return acc;
+            },
+            defaultOptions);
+    },
+
     /**
      * Reloads chatter and message count after posting message
      *
diff --git a/addons/project/static/src/project_sharing/components/chatter.js b/addons/project/static/src/project_sharing/components/chatter.js
index 3f85c37f935..e1ad0d48a25 100644
--- a/addons/project/static/src/project_sharing/components/chatter.js
+++ b/addons/project/static/src/project_sharing/components/chatter.js
@@ -4,6 +4,19 @@ import { PortalChatter } from 'portal.chatter';
 import Composer from './composer';
 
 export default PortalChatter.extend({
+    messageFetch(domain) {
+        if (!this.options.res_id) {
+            return Promise.resolve();
+        }
+        return this._super.apply(this, arguments);
+    },
+    _chatterInit() {
+        if (!this.options.res_id) {
+            this.result = { messages: [] };
+            return Promise.resolve();
+        }
+        return this._super.apply(this, arguments);
+    },
     _messageFetchPrepareParams() {
         const data = this._super.apply(this, arguments);
         if (this.options.project_sharing_id) {
@@ -14,4 +27,8 @@ export default PortalChatter.extend({
     _createComposerWidget() {
         return new Composer(this, this.options);
     },
+    update(props) {
+        this._setOptions(props);
+        this._reloadChatterContent();
+    },
 });
diff --git a/addons/project/static/src/project_sharing/components/chatter.xml b/addons/project/static/src/project_sharing/components/chatter.xml
new file mode 100644
index 00000000000..aca16ce257a
--- /dev/null
+++ b/addons/project/static/src/project_sharing/components/chatter.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<templates id="template" xml:space="preserve">
+    <t t-extend="portal.chatter_messages">
+        <t t-jquery="t[t-as='message']" t-operation="attributes">
+            <attribute name="t-foreach">!!widget.options.res_id &amp;&amp; widget.get('messages') || []</attribute>
+        </t>
+    </t>
+</templates>
diff --git a/addons/project/static/src/project_sharing/views/form/renderer.js b/addons/project/static/src/project_sharing/views/form/renderer.js
index 41105160548..1ac113fbd7f 100644
--- a/addons/project/static/src/project_sharing/views/form/renderer.js
+++ b/addons/project/static/src/project_sharing/views/form/renderer.js
@@ -20,7 +20,7 @@ export default FormRenderer.extend({
             hash: '',
             res_id: this.state.res_id,
             pager_step: 10,
-            allow_composer: true,
+            allow_composer: !!this.state.res_id,
             two_columns: false,
             project_sharing_id: session.project_id,
         };
@@ -33,5 +33,4 @@ export default FormRenderer.extend({
     _mountChatterContainerComponent() {
         this._chatterContainerComponent.appendTo(this._chatterContainerTarget);
     },
-    _updateChatterContainerComponent() {},
 });