diff --git a/services/static-webserver/client/source/class/osparc/conversation/AddMessage.js b/services/static-webserver/client/source/class/osparc/conversation/AddMessage.js
new file mode 100644
index 00000000000..7a0cf26f871
--- /dev/null
+++ b/services/static-webserver/client/source/class/osparc/conversation/AddMessage.js
@@ -0,0 +1,243 @@
+/* ************************************************************************
+
+   osparc - the simcore frontend
+
+   https://osparc.io
+
+   Copyright:
+     2023 IT'IS Foundation, https://itis.swiss
+
+   License:
+     MIT: https://opensource.org/licenses/MIT
+
+   Authors:
+     * Odei Maiz (odeimaiz)
+
+************************************************************************ */
+
+
+qx.Class.define("osparc.conversation.AddMessage", {
+  extend: qx.ui.core.Widget,
+
+  /**
+    * @param studyData {Object} serialized Study Data
+    * @param conversationId {String} Conversation Id
+    */
+  construct: function(studyData, conversationId = null) {
+    this.base(arguments);
+
+    this.__studyData = studyData;
+    this.__conversationId = conversationId;
+
+    this._setLayout(new qx.ui.layout.VBox(5));
+
+    this.__buildLayout();
+  },
+
+  events: {
+    "commentAdded": "qx.event.type.Event"
+  },
+
+  members: {
+    __studyData: null,
+    __conversationId: null,
+
+    _createChildControlImpl: function(id) {
+      let control;
+      switch (id) {
+        case "add-comment-label":
+          control = new qx.ui.basic.Label().set({
+            value: this.tr("Add comment")
+          });
+          this._add(control);
+          break;
+        case "add-comment-layout": {
+          const grid = new qx.ui.layout.Grid(8, 5);
+          grid.setColumnWidth(0, 32);
+          grid.setColumnFlex(1, 1);
+          control = new qx.ui.container.Composite(grid);
+          this._add(control, {
+            flex: 1
+          });
+          break;
+        }
+        case "thumbnail": {
+          control = new qx.ui.basic.Image().set({
+            alignY: "middle",
+            scale: true,
+            allowGrowX: true,
+            allowGrowY: true,
+            allowShrinkX: true,
+            allowShrinkY: true,
+            maxWidth: 32,
+            maxHeight: 32,
+            decorator: "rounded",
+          });
+          const authData = osparc.auth.Data.getInstance();
+          const myUsername = authData.getUsername();
+          const myEmail = authData.getEmail();
+          control.set({
+            source: osparc.utils.Avatar.emailToThumbnail(myEmail, myUsername, 32)
+          });
+          const layout = this.getChildControl("add-comment-layout");
+          layout.add(control, {
+            row: 0,
+            column: 0
+          });
+          break;
+        }
+        case "comment-field":
+          control = new osparc.editor.MarkdownEditor();
+          control.getChildControl("buttons").exclude();
+          const layout = this.getChildControl("add-comment-layout");
+          layout.add(control, {
+            row: 0,
+            column: 1
+          });
+          break;
+        case "add-comment-button":
+          control = new qx.ui.form.Button(this.tr("Add message")).set({
+            appearance: "form-button",
+            allowGrowX: false,
+            alignX: "right"
+          });
+          control.setEnabled(osparc.data.model.Study.canIWrite(this.__studyData["accessRights"]));
+          this._add(control);
+          break;
+        case "notify-user-button":
+          control = new qx.ui.form.Button("🔔 " + this.tr("Notify user")).set({
+            appearance: "form-button",
+            allowGrowX: false,
+            alignX: "right"
+          });
+          control.setEnabled(osparc.data.model.Study.canIWrite(this.__studyData["accessRights"]));
+          this._add(control);
+          break;
+      }
+
+      return control || this.base(arguments, id);
+    },
+
+    __buildLayout: function() {
+      this.getChildControl("thumbnail");
+      this.getChildControl("comment-field");
+
+      const addMessageButton = this.getChildControl("add-comment-button");
+      addMessageButton.addListener("execute", () => this.__addComment());
+
+      const notifyUserButton = this.getChildControl("notify-user-button");
+      notifyUserButton.addListener("execute", () => this.__notifyUserTapped());
+    },
+
+    __addComment: function() {
+      if (this.__conversationId) {
+        this.__postMessage();
+      } else {
+        // create new conversation first
+        osparc.study.Conversations.addConversation(this.__studyData["uuid"])
+          .then(data => {
+            this.__conversationId = data["conversationId"];
+            this.__postMessage();
+          })
+      }
+    },
+
+    __notifyUserTapped: function() {
+      const showOrganizations = false;
+      const showAccessRights = false;
+      const userManager = new osparc.share.NewCollaboratorsManager(this.__studyData, showOrganizations, showAccessRights).set({
+        acceptOnlyOne: true,
+      });
+      userManager.setCaption(this.tr("Notify user"));
+      userManager.getActionButton().setLabel(this.tr("Notify"));
+      userManager.addListener("addCollaborators", e => {
+        userManager.close();
+        const data = e.getData();
+        const userGids = data["selectedGids"];
+        if (userGids && userGids.length) {
+          const userGid = parseInt(userGids[0]);
+          this.__notifyUser(userGid);
+        }
+      });
+    },
+
+    __notifyUser: function(userGid) {
+      // Note!
+      // This check only works if the project is directly shared with the user.
+      // If it's shared through a group, it might be a bit confusing
+      if (userGid in this.__studyData["accessRights"]) {
+        this.__addNotify(userGid);
+      } else {
+        const msg = this.tr("This user has no access to the project. Do you want to share it?");
+        const win = new osparc.ui.window.Confirmation(msg).set({
+          caption: this.tr("Share"),
+          confirmText: this.tr("Share"),
+          confirmAction: "create"
+        });
+        win.center();
+        win.open();
+        win.addListener("close", () => {
+          if (win.getConfirmed()) {
+            const newCollaborators = {
+              [userGid]: osparc.data.Roles.STUDY["write"].accessRights
+            };
+            osparc.store.Study.addCollaborators(this.__studyData, newCollaborators)
+              .then(() => {
+                this.__addNotify(userGid);
+                const potentialCollaborators = osparc.store.Groups.getInstance().getPotentialCollaborators()
+                if (userGid in potentialCollaborators && "getUserId" in potentialCollaborators[userGid]) {
+                  const uid = potentialCollaborators[userGid].getUserId();
+                  osparc.notification.Notifications.pushStudyShared(uid, this.__studyData["uuid"]);
+                }
+              })
+              .catch(err => osparc.FlashMessenger.logError(err));
+          }
+        }, this);
+      }
+    },
+
+    __addNotify: function(userGid) {
+      if (this.__conversationId) {
+        this.__postNotify(userGid);
+      } else {
+        // create new conversation first
+        osparc.study.Conversations.addConversation(this.__studyData["uuid"])
+          .then(data => {
+            this.__conversationId = data["conversationId"];
+            this.__postNotify(userGid);
+          });
+      }
+    },
+
+    __postMessage: function() {
+      const commentField = this.getChildControl("comment-field");
+      const comment = commentField.getChildControl("text-area").getValue();
+      if (comment) {
+        osparc.study.Conversations.addMessage(this.__studyData["uuid"], this.__conversationId, comment)
+          .then(data => {
+            this.fireDataEvent("commentAdded", data);
+            commentField.getChildControl("text-area").setValue("");
+            osparc.FlashMessenger.logAs(this.tr("Message added"), "INFO");
+          });
+      }
+    },
+
+    __postNotify: function(userGid) {
+      if (userGid) {
+        osparc.study.Conversations.notifyUser(this.__studyData["uuid"], this.__conversationId, userGid)
+          .then(data => {
+            this.fireDataEvent("commentAdded", data);
+            const potentialCollaborators = osparc.store.Groups.getInstance().getPotentialCollaborators();
+            if (userGid in potentialCollaborators) {
+              if ("getUserId" in potentialCollaborators[userGid]) {
+                const uid = potentialCollaborators[userGid].getUserId();
+                osparc.notification.Notifications.pushConversationNotification(uid, this.__studyData["uuid"]);
+              }
+              const msg = "getLabel" in potentialCollaborators[userGid] ? potentialCollaborators[userGid].getLabel() + this.tr(" was notified") : this.tr("Notification sent");
+              osparc.FlashMessenger.logAs(msg, "INFO");
+            }
+          });
+      }
+    },
+  }
+});
diff --git a/services/static-webserver/client/source/class/osparc/info/Conversation.js b/services/static-webserver/client/source/class/osparc/conversation/Conversation.js
similarity index 87%
rename from services/static-webserver/client/source/class/osparc/info/Conversation.js
rename to services/static-webserver/client/source/class/osparc/conversation/Conversation.js
index d63d9b7732d..d61f5620098 100644
--- a/services/static-webserver/client/source/class/osparc/info/Conversation.js
+++ b/services/static-webserver/client/source/class/osparc/conversation/Conversation.js
@@ -16,7 +16,7 @@
 ************************************************************************ */
 
 
-qx.Class.define("osparc.info.Conversation", {
+qx.Class.define("osparc.conversation.Conversation", {
   extend: qx.ui.tabview.Page,
 
   /**
@@ -32,7 +32,7 @@ qx.Class.define("osparc.info.Conversation", {
       this.setConversationId(conversationId);
     }
 
-    this._setLayout(new qx.ui.layout.VBox(10));
+    this._setLayout(new qx.ui.layout.VBox(5));
 
     this.set({
       padding: 10,
@@ -152,7 +152,9 @@ qx.Class.define("osparc.info.Conversation", {
       this.__messagesList = new qx.ui.container.Composite(new qx.ui.layout.VBox(5)).set({
         alignY: "middle"
       });
-      this._add(this.__messagesList, {
+      const scrollView = new qx.ui.container.Scroll();
+      scrollView.add(this.__messagesList);
+      this._add(scrollView, {
         flex: 1
       });
 
@@ -161,7 +163,7 @@ qx.Class.define("osparc.info.Conversation", {
       this._add(this.__loadMoreMessages);
 
       if (osparc.data.model.Study.canIWrite(this.__studyData["accessRights"])) {
-        const addMessages = new osparc.info.CommentAdd(this.__studyData["uuid"], this.getConversationId());
+        const addMessages = new osparc.conversation.AddMessage(this.__studyData, this.getConversationId());
         addMessages.setPaddingLeft(10);
         addMessages.addListener("commentAdded", e => {
           const data = e.getData();
@@ -223,15 +225,26 @@ qx.Class.define("osparc.info.Conversation", {
     },
 
     __addMessages: function(messages) {
-      if (messages.length === 1) {
+      const nMessages = messages.filter(msg => msg["type"] === "MESSAGE").length;
+      if (nMessages === 1) {
         this.__messagesTitle.setValue(this.tr("1 Message"));
-      } else if (messages.length > 1) {
-        this.__messagesTitle.setValue(messages.length + this.tr(" Messages"));
+      } else if (nMessages > 1) {
+        this.__messagesTitle.setValue(nMessages + this.tr(" Messages"));
       }
 
       messages.forEach(message => {
-        const messageUi = new osparc.info.CommentUI(message);
-        this.__messagesList.add(messageUi);
+        let control = null;
+        switch (message["type"]) {
+          case "MESSAGE":
+            control = new osparc.conversation.MessageUI(message);
+            break;
+          case "NOTIFICATION":
+            control = new osparc.conversation.NotificationUI(message);
+            break;
+        }
+        if (control) {
+          this.__messagesList.add(control);
+        }
       });
     },
   }
diff --git a/services/static-webserver/client/source/class/osparc/info/CommentUI.js b/services/static-webserver/client/source/class/osparc/conversation/MessageUI.js
similarity index 71%
rename from services/static-webserver/client/source/class/osparc/info/CommentUI.js
rename to services/static-webserver/client/source/class/osparc/conversation/MessageUI.js
index 22263198564..55a5cbec23d 100644
--- a/services/static-webserver/client/source/class/osparc/info/CommentUI.js
+++ b/services/static-webserver/client/source/class/osparc/conversation/MessageUI.js
@@ -16,35 +16,38 @@
 ************************************************************************ */
 
 
-qx.Class.define("osparc.info.CommentUI", {
+qx.Class.define("osparc.conversation.MessageUI", {
   extend: qx.ui.core.Widget,
 
   /**
-    * @param comment {Object} comment
+    * @param message {Object} message
     */
-  construct: function(comment) {
+  construct: function(message) {
     this.base(arguments);
 
-    this.__comment = comment;
+    this.__message = message;
 
-    const isMyComment = this.__isMyComment();
+    const isMyMessage = this.self().isMyMessage(this.__message);
     const layout = new qx.ui.layout.Grid(12, 4);
-    layout.setColumnFlex(1, 1); // comment
-    layout.setColumnFlex(isMyComment ? 0 : 2, 3); // spacer
+    layout.setColumnFlex(1, 1); // content
+    layout.setColumnFlex(isMyMessage ? 0 : 2, 3); // spacer
     this._setLayout(layout);
     this.setPadding(5);
 
     this.__buildLayout();
   },
 
-  members: {
-    __comment: null,
+  statics: {
+    isMyMessage: function(message) {
+      return message && osparc.auth.Data.getInstance().getGroupId() === message["userGroupId"];
+    }
+  },
 
-    __isMyComment: function() {
-      return this.__comment && osparc.auth.Data.getInstance().getGroupId() === this.__comment["userGroupId"];
-    },
+  members: {
+    __message: null,
 
     _createChildControlImpl: function(id) {
+      const isMyMessage = this.self().isMyMessage(this.__message);
       let control;
       switch (id) {
         case "thumbnail":
@@ -53,17 +56,17 @@ qx.Class.define("osparc.info.CommentUI", {
             maxWidth: 32,
             maxHeight: 32,
             decorator: "rounded",
-            marginTop: 2,
+            marginTop: 4,
           });
           this._add(control, {
             row: 0,
-            column: this.__isMyComment() ? 2 : 0,
+            column: isMyMessage ? 2 : 0,
             rowSpan: 2,
           });
           break;
         case "header-layout":
           control = new qx.ui.container.Composite(new qx.ui.layout.HBox(5).set({
-            alignX: this.__isMyComment() ? "right" : "left"
+            alignX: isMyMessage ? "right" : "left"
           }));
           control.addAt(new qx.ui.basic.Label("-"), 1);
           this._add(control, {
@@ -75,15 +78,15 @@ qx.Class.define("osparc.info.CommentUI", {
           control = new qx.ui.basic.Label().set({
             font: "text-12"
           });
-          this.getChildControl("header-layout").addAt(control, this.__isMyComment() ? 2 : 0);
+          this.getChildControl("header-layout").addAt(control, isMyMessage ? 2 : 0);
           break;
         case "last-updated":
           control = new qx.ui.basic.Label().set({
             font: "text-12"
           });
-          this.getChildControl("header-layout").addAt(control, this.__isMyComment() ? 0 : 2);
+          this.getChildControl("header-layout").addAt(control, isMyMessage ? 0 : 2);
           break;
-        case "comment-content":
+        case "message-content":
           control = new osparc.ui.markdown.Markdown().set({
             decorator: "rounded",
             noMargin: true,
@@ -92,7 +95,7 @@ qx.Class.define("osparc.info.CommentUI", {
             allowGrowX: true,
           });
           control.getContentElement().setStyles({
-            "text-align": this.__isMyComment() ? "right" : "left",
+            "text-align": isMyMessage ? "right" : "left",
           });
           this._add(control, {
             row: 1,
@@ -103,7 +106,7 @@ qx.Class.define("osparc.info.CommentUI", {
           control = new qx.ui.core.Spacer();
           this._add(control, {
             row: 1,
-            column: this.__isMyComment() ? 0 : 2,
+            column: isMyMessage ? 0 : 2,
           });
           break;
       }
@@ -116,15 +119,15 @@ qx.Class.define("osparc.info.CommentUI", {
 
       const userName = this.getChildControl("user-name");
 
-      const date = new Date(this.__comment["modified"]);
+      const date = new Date(this.__message["modified"]);
       const date2 = osparc.utils.Utils.formatDateAndTime(date);
       const lastUpdate = this.getChildControl("last-updated");
       lastUpdate.setValue(date2);
 
-      const commentContent = this.getChildControl("comment-content");
-      commentContent.setValue(this.__comment["content"]);
+      const messageContent = this.getChildControl("message-content");
+      messageContent.setValue(this.__message["content"]);
 
-      osparc.store.Users.getInstance().getUser(this.__comment["userGroupId"])
+      osparc.store.Users.getInstance().getUser(this.__message["userGroupId"])
         .then(user => {
           if (user) {
             thumbnail.setSource(user.getThumbnail());
diff --git a/services/static-webserver/client/source/class/osparc/conversation/NotificationUI.js b/services/static-webserver/client/source/class/osparc/conversation/NotificationUI.js
new file mode 100644
index 00000000000..670e3437e3d
--- /dev/null
+++ b/services/static-webserver/client/source/class/osparc/conversation/NotificationUI.js
@@ -0,0 +1,139 @@
+/* ************************************************************************
+
+   osparc - the simcore frontend
+
+   https://osparc.io
+
+   Copyright:
+     2023 IT'IS Foundation, https://itis.swiss
+
+   License:
+     MIT: https://opensource.org/licenses/MIT
+
+   Authors:
+     * Odei Maiz (odeimaiz)
+
+************************************************************************ */
+
+
+qx.Class.define("osparc.conversation.NotificationUI", {
+  extend: qx.ui.core.Widget,
+
+  /**
+    * @param message {Object} message
+    */
+  construct: function(message) {
+    this.base(arguments);
+
+    this.__message = message;
+
+    const isMyMessage = osparc.conversation.MessageUI.isMyMessage(this.__message);
+    const layout = new qx.ui.layout.Grid(4, 4);
+    layout.setColumnFlex(isMyMessage ? 0 : 3, 3); // spacer
+    layout.setRowAlign(0, "center", "middle");
+    this._setLayout(layout);
+    this.setPadding(5);
+
+    this.__buildLayout();
+  },
+
+  members: {
+    __message: null,
+
+    // spacer - date - content - (thumbnail-spacer)
+    // (thumbnail-spacer) - content - date - spacer
+    _createChildControlImpl: function(id) {
+      const isMyMessage = osparc.conversation.MessageUI.isMyMessage(this.__message);
+      let control;
+      switch (id) {
+        case "thumbnail-spacer":
+          control = new qx.ui.core.Spacer().set({
+            width: 32,
+          });
+          this._add(control, {
+            row: 0,
+            column: isMyMessage ? 3 : 0,
+          });
+          break;
+        case "message-content":
+          control = new qx.ui.basic.Label().set({
+          });
+          control.getContentElement().setStyles({
+            "text-align": isMyMessage ? "right" : "left",
+          });
+          this._add(control, {
+            row: 0,
+            column: isMyMessage ? 2 : 1,
+          });
+          break;
+        case "last-updated":
+          control = new qx.ui.basic.Label().set({
+            font: "text-12"
+          });
+          this._add(control, {
+            row: 0,
+            column: isMyMessage ? 1 : 2,
+          });
+          break;
+        case "spacer":
+          control = new qx.ui.core.Spacer();
+          this._add(control, {
+            row: 0,
+            column: isMyMessage ? 0 : 3,
+          });
+          break;
+      }
+
+      return control || this.base(arguments, id);
+    },
+
+    __buildLayout: function() {
+      this.getChildControl("thumbnail-spacer");
+
+      const isMyMessage = osparc.conversation.MessageUI.isMyMessage(this.__message);
+
+      const modifiedDate = new Date(this.__message["modified"]);
+      const date = osparc.utils.Utils.formatDateAndTime(modifiedDate);
+      const lastUpdate = this.getChildControl("last-updated");
+      lastUpdate.setValue(isMyMessage ? date + " -" : " - " + date);
+
+      const messageContent = this.getChildControl("message-content");
+      const notifierUserGroupId = parseInt(this.__message["userGroupId"]);
+      const notifiedUserGroupId = parseInt(this.__message["content"]);
+      let msgContent = "🔔 ";
+      Promise.all([
+        osparc.store.Users.getInstance().getUser(notifierUserGroupId),
+        osparc.store.Users.getInstance().getUser(notifiedUserGroupId),
+      ])
+        .then(values => {
+          const notifierUser = values[0];
+          if (isMyMessage) {
+            msgContent += "You";
+          } else if (notifierUser) {
+            msgContent += notifierUser.getLabel();
+          } else {
+            msgContent += "unknown user";
+          }
+
+          msgContent += " notified ";
+
+          const notifiedUser = values[1];
+          if (osparc.auth.Data.getInstance().getGroupId() === notifiedUserGroupId) {
+            msgContent += "You";
+          } else if (notifiedUser) {
+            msgContent += notifiedUser.getLabel();
+          } else {
+            msgContent += "unknown user";
+          }
+        })
+        .catch(() => {
+          msgContent += "unknown user notified";
+        })
+        .finally(() => {
+          messageContent.setValue(msgContent);
+        });
+
+      this.getChildControl("spacer");
+    }
+  }
+});
diff --git a/services/static-webserver/client/source/class/osparc/dashboard/ResourceDetails.js b/services/static-webserver/client/source/class/osparc/dashboard/ResourceDetails.js
index 0026d83b81d..d517f80bdd1 100644
--- a/services/static-webserver/client/source/class/osparc/dashboard/ResourceDetails.js
+++ b/services/static-webserver/client/source/class/osparc/dashboard/ResourceDetails.js
@@ -144,6 +144,7 @@ qx.Class.define("osparc.dashboard.ResourceDetails", {
     __resourceModel: null,
     __infoPage: null,
     __servicesUpdatePage: null,
+    __conversationsPage: null,
     __permissionsPage: null,
     __tagsPage: null,
     __billingSettings: null,
@@ -294,6 +295,10 @@ qx.Class.define("osparc.dashboard.ResourceDetails", {
       this._openPage(this.__servicesUpdatePage);
     },
 
+    openConversations: function() {
+      this._openPage(this.__conversationsPage);
+    },
+
     openAccessRights: function() {
       this._openPage(this.__permissionsPage);
     },
@@ -556,7 +561,7 @@ qx.Class.define("osparc.dashboard.ResourceDetails", {
       const id = "Conversations";
       const title = this.tr("Conversations");
       const iconSrc = "@FontAwesome5Solid/comments/22";
-      const page = new osparc.dashboard.resources.pages.BasePage(title, iconSrc, id);
+      const page = this.__conversationsPage = new osparc.dashboard.resources.pages.BasePage(title, iconSrc, id);
       this.__addToolbarButtons(page);
 
       const lazyLoadContent = () => {
diff --git a/services/static-webserver/client/source/class/osparc/editor/AnnotationNoteCreator.js b/services/static-webserver/client/source/class/osparc/editor/AnnotationNoteCreator.js
index 4d3f31c15ee..a1d69c4b2f0 100644
--- a/services/static-webserver/client/source/class/osparc/editor/AnnotationNoteCreator.js
+++ b/services/static-webserver/client/source/class/osparc/editor/AnnotationNoteCreator.js
@@ -85,54 +85,7 @@ qx.Class.define("osparc.editor.AnnotationNoteCreator", {
           control = new qx.ui.form.Button(this.tr("Select recipient")).set({
             allowGrowX: false
           });
-          control.addListener("execute", () => {
-            const currentStudy = osparc.store.Store.getInstance().getCurrentStudy().serialize();
-            currentStudy["resourceType"] = "study";
-            const recipientsManager = new osparc.share.NewCollaboratorsManager(currentStudy, false, false);
-            recipientsManager.setCaption("Recipient");
-            recipientsManager.getActionButton().setLabel(this.tr("Add"));
-            recipientsManager.addListener("addCollaborators", e => {
-              const data = e.getData();
-              const recipientGids = data["selectedGids"];
-
-              if (recipientGids && recipientGids.length) {
-                const recipientGid = parseInt(recipientGids[0]);
-                this.__setRecipientGid(recipientGid);
-                recipientsManager.close();
-
-                const currentAccessRights = this.__study.getAccessRights();
-                const proposeSharing = [];
-                if (!(parseInt(recipientGid) in currentAccessRights)) {
-                  proposeSharing.push(recipientGid);
-                }
-                if (proposeSharing.length) {
-                  const collaboratorsManager = new osparc.share.NewCollaboratorsManager(currentStudy, false, true, proposeSharing);
-                  collaboratorsManager.addListener("addCollaborators", ev => {
-                    const {
-                      selectedGids,
-                      newAccessRights,
-                    } = ev.getData();
-                    const newCollaborators = {};
-                    selectedGids.forEach(gid => {
-                      newCollaborators[gid] = newAccessRights;
-                    });
-                    const studyData = this.__study.serialize();
-                    osparc.store.Study.addCollaborators(studyData, newCollaborators)
-                      .then(() => {
-                        const potentialCollaborators = osparc.store.Groups.getInstance().getPotentialCollaborators()
-                        selectedGids.forEach(gid => {
-                          if (gid in potentialCollaborators && "getUserId" in potentialCollaborators[gid]) {
-                            const uid = potentialCollaborators[gid].getUserId();
-                            osparc.notification.Notifications.postNewStudy(uid, studyData["uuid"]);
-                          }
-                        });
-                      })
-                      .finally(() => collaboratorsManager.close());
-                  });
-                }
-              }
-            }, this);
-          }, this);
+          control.addListener("execute", () => this.__selectRecipientTapped(), this);
           this.getChildControl("recipient-layout").add(control);
           break;
         case "selected-recipient":
@@ -178,6 +131,59 @@ qx.Class.define("osparc.editor.AnnotationNoteCreator", {
       return control || this.base(arguments, id);
     },
 
+    __selectRecipientTapped: function() {
+      const currentStudyData = osparc.store.Store.getInstance().getCurrentStudy().serialize();
+      currentStudyData["resourceType"] = "study";
+      const usersManager = new osparc.share.NewCollaboratorsManager(currentStudyData, false, false).set({
+        acceptOnlyOne: true,
+      });
+      usersManager.setCaption("Recipient");
+      usersManager.getActionButton().setLabel(this.tr("Add"));
+      usersManager.addListener("addCollaborators", e => {
+        usersManager.close();
+        const data = e.getData();
+        const userGids = data["selectedGids"];
+        if (userGids && userGids.length) {
+          const userGid = parseInt(userGids[0]);
+          this.__recipientSelected(userGid);
+        }
+      }, this);
+    },
+
+    __recipientSelected: function(userGid) {
+      const currentAccessRights = this.__study.getAccessRights();
+      if (userGid in currentAccessRights) {
+        this.__setRecipientGid(userGid);
+      } else {
+        const msg = this.tr("This user has no access to the project. Do you want to share it?");
+        const win = new osparc.ui.window.Confirmation(msg).set({
+          caption: this.tr("Share"),
+          confirmText: this.tr("Share"),
+          confirmAction: "create"
+        });
+        win.center();
+        win.open();
+        win.addListener("close", () => {
+          if (win.getConfirmed()) {
+            const newCollaborators = {
+              [userGid]: osparc.data.Roles.STUDY["write"].accessRights
+            };
+            const currentStudyData = osparc.store.Store.getInstance().getCurrentStudy().serialize();
+            osparc.store.Study.addCollaborators(currentStudyData, newCollaborators)
+              .then(() => {
+                this.__setRecipientGid(userGid);
+                const potentialCollaborators = osparc.store.Groups.getInstance().getPotentialCollaborators()
+                if (userGid in potentialCollaborators && "getUserId" in potentialCollaborators[userGid]) {
+                  const uid = potentialCollaborators[userGid].getUserId();
+                  osparc.notification.Notifications.pushStudyShared(uid, currentStudyData["uuid"]);
+                }
+              })
+              .finally(() => collaboratorsManager.close());
+          }
+        });
+      }
+    },
+
     __setRecipientGid: function(gid) {
       this.setRecipientGid(gid);
       // only users were proposed
diff --git a/services/static-webserver/client/source/class/osparc/info/CommentAdd.js b/services/static-webserver/client/source/class/osparc/info/CommentAdd.js
deleted file mode 100644
index 8bfb2a2c330..00000000000
--- a/services/static-webserver/client/source/class/osparc/info/CommentAdd.js
+++ /dev/null
@@ -1,149 +0,0 @@
-/* ************************************************************************
-
-   osparc - the simcore frontend
-
-   https://osparc.io
-
-   Copyright:
-     2023 IT'IS Foundation, https://itis.swiss
-
-   License:
-     MIT: https://opensource.org/licenses/MIT
-
-   Authors:
-     * Odei Maiz (odeimaiz)
-
-************************************************************************ */
-
-
-qx.Class.define("osparc.info.CommentAdd", {
-  extend: qx.ui.core.Widget,
-
-  /**
-    * @param studyId {String} Study Id
-    * @param conversationId {String} Conversation Id
-    */
-  construct: function(studyId, conversationId = null) {
-    this.base(arguments);
-
-    this.__studyId = studyId;
-    this.__conversationId = conversationId;
-
-    this._setLayout(new qx.ui.layout.VBox(5));
-
-    this.__buildLayout();
-  },
-
-  events: {
-    "commentAdded": "qx.event.type.Event"
-  },
-
-  members: {
-    __studyId: null,
-    __conversationId: null,
-
-    _createChildControlImpl: function(id) {
-      let control;
-      switch (id) {
-        case "add-comment-label":
-          control = new qx.ui.basic.Label().set({
-            value: this.tr("Add comment")
-          });
-          this._add(control);
-          break;
-        case "add-comment-layout": {
-          const grid = new qx.ui.layout.Grid(8, 5);
-          grid.setColumnWidth(0, 32);
-          grid.setColumnFlex(1, 1);
-          control = new qx.ui.container.Composite(grid);
-          this._add(control, {
-            flex: 1
-          });
-          break;
-        }
-        case "thumbnail": {
-          control = new qx.ui.basic.Image().set({
-            alignY: "middle",
-            scale: true,
-            allowGrowX: true,
-            allowGrowY: true,
-            allowShrinkX: true,
-            allowShrinkY: true,
-            maxWidth: 32,
-            maxHeight: 32,
-            decorator: "rounded",
-          });
-          const authData = osparc.auth.Data.getInstance();
-          const myUsername = authData.getUsername();
-          const myEmail = authData.getEmail();
-          control.set({
-            source: osparc.utils.Avatar.emailToThumbnail(myEmail, myUsername, 32)
-          });
-          const layout = this.getChildControl("add-comment-layout");
-          layout.add(control, {
-            row: 0,
-            column: 0
-          });
-          break;
-        }
-        case "comment-field": {
-          control = new osparc.editor.MarkdownEditor();
-          control.getChildControl("buttons").exclude();
-          const layout = this.getChildControl("add-comment-layout");
-          layout.add(control, {
-            row: 0,
-            column: 1
-          });
-          break;
-        }
-        case "buttons-layout": {
-          control = new qx.ui.container.Composite(new qx.ui.layout.HBox(5).set({
-            alignX: "right"
-          }));
-          this._add(control);
-          break;
-        }
-        case "add-comment-button": {
-          control = new qx.ui.form.Button(this.tr("Add message")).set({
-            appearance: "form-button",
-            allowGrowX: false,
-          });
-          this.getChildControl("buttons-layout").add(control);
-          break;
-        }
-      }
-
-      return control || this.base(arguments, id);
-    },
-
-    __buildLayout: function() {
-      this.getChildControl("thumbnail");
-      this.getChildControl("comment-field");
-      const addButton = this.getChildControl("add-comment-button");
-      addButton.addListener("execute", () => {
-        if (this.__conversationId) {
-          this.__addComment();
-        } else {
-          // create new conversation first
-          osparc.study.Conversations.addConversation(this.__studyId)
-            .then(data => {
-              this.__conversationId = data["conversationId"];
-              this.__addComment();
-            })
-        }
-      });
-    },
-
-    __addComment: function() {
-      const commentField = this.getChildControl("comment-field");
-      const comment = commentField.getChildControl("text-area").getValue();
-      if (comment) {
-        osparc.study.Conversations.addMessage(this.__studyId, this.__conversationId, comment)
-          .then(data => {
-            this.fireDataEvent("commentAdded", data);
-            commentField.getChildControl("text-area").setValue("");
-          });
-      }
-    },
-  }
-});
diff --git a/services/static-webserver/client/source/class/osparc/notification/Notification.js b/services/static-webserver/client/source/class/osparc/notification/Notification.js
index af219894c0f..7318bd995d7 100644
--- a/services/static-webserver/client/source/class/osparc/notification/Notification.js
+++ b/services/static-webserver/client/source/class/osparc/notification/Notification.js
@@ -54,6 +54,7 @@ qx.Class.define("osparc.notification.Notification", {
         "NEW_ORGANIZATION",
         "STUDY_SHARED",
         "TEMPLATE_SHARED",
+        "CONVERSATION_NOTIFICATION",
         "ANNOTATION_NOTE",
         "WALLET_SHARED"
       ],
diff --git a/services/static-webserver/client/source/class/osparc/notification/NotificationUI.js b/services/static-webserver/client/source/class/osparc/notification/NotificationUI.js
index 98bf24ebb7d..7cd46cbae75 100644
--- a/services/static-webserver/client/source/class/osparc/notification/NotificationUI.js
+++ b/services/static-webserver/client/source/class/osparc/notification/NotificationUI.js
@@ -114,6 +114,60 @@ qx.Class.define("osparc.notification.NotificationUI", {
     },
 
     __applyNotification: function(notification) {
+      const icon = this.getChildControl("icon");
+      switch (notification.getCategory()) {
+        case "NEW_ORGANIZATION":
+          icon.setSource("@FontAwesome5Solid/users/14");
+          break;
+        case "STUDY_SHARED":
+          icon.setSource("@FontAwesome5Solid/file/14");
+          break;
+        case "TEMPLATE_SHARED":
+          icon.setSource("@FontAwesome5Solid/copy/14");
+          break;
+        case "CONVERSATION_NOTIFICATION":
+          icon.setSource("@FontAwesome5Solid/bell/14");
+          break;
+        case "ANNOTATION_NOTE":
+          icon.setSource("@FontAwesome5Solid/file/14");
+          break;
+        case "WALLET_SHARED":
+          icon.setSource("@MaterialIcons/account_balance_wallet/14");
+          break;
+      }
+
+      const titleLabel = this.getChildControl("title");
+      titleLabel.setValue(notification.getTitle());
+
+      const descriptionLabel = this.getChildControl("text");
+      descriptionLabel.setValue(notification.getText());
+
+      const date = this.getChildControl("date");
+      notification.bind("date", date, "value", {
+        converter: value => {
+          if (value) {
+            return osparc.utils.Utils.formatDateAndTime(new Date(value));
+          }
+          return "";
+        }
+      });
+
+      const highlight = mouseOn => {
+        this.set({
+          backgroundColor: mouseOn ? "strong-main" : "transparent"
+        })
+      };
+      this.addListener("mouseover", () => highlight(true));
+      this.addListener("mouseout", () => highlight(false));
+      highlight(false);
+
+      // this will trigger calls to the backend, so only make them if necessary
+      this.addListenerOnce("appear", () => this.__enrichTexts());
+    },
+
+    __enrichTexts: function() {
+      const notification = this.getNotification();
+
       let resourceId = null;
       if (notification.getResourceId()) {
         resourceId = notification.getResourceId();
@@ -122,28 +176,23 @@ qx.Class.define("osparc.notification.NotificationUI", {
         const actionablePath = notification.getActionablePath();
         resourceId = actionablePath.split("/")[1];
       }
-      const userFromId = notification.getUserFromId();
 
-      const icon = this.getChildControl("icon");
+      const userFromId = notification.getUserFromId();
       const titleLabel = this.getChildControl("title");
-      titleLabel.setValue(notification.getTitle());
       const descriptionLabel = this.getChildControl("text");
-      descriptionLabel.setValue(notification.getText());
 
       switch (notification.getCategory()) {
         case "NEW_ORGANIZATION":
-          icon.setSource("@FontAwesome5Solid/users/14");
           if (resourceId) {
             const org = osparc.store.Groups.getInstance().getOrganization(resourceId);
             if (org) {
-              descriptionLabel.setValue("You're now member of '" + org.getLabel() + "'")
+              descriptionLabel.setValue("You're now member of '" + org.getLabel() + "'");
             } else {
               this.setEnabled(false);
             }
           }
           break;
         case "STUDY_SHARED":
-          icon.setSource("@FontAwesome5Solid/file/14");
           if (resourceId) {
             const params = {
               url: {
@@ -167,7 +216,6 @@ qx.Class.define("osparc.notification.NotificationUI", {
           }
           break;
         case "TEMPLATE_SHARED":
-          icon.setSource("@FontAwesome5Solid/copy/14");
           if (resourceId) {
             osparc.store.Templates.fetchTemplate(resourceId)
               .then(templateData => {
@@ -184,8 +232,25 @@ qx.Class.define("osparc.notification.NotificationUI", {
             }
           }
           break;
+        case "CONVERSATION_NOTIFICATION":
+          if (resourceId) {
+            const params = {
+              url: {
+                "studyId": resourceId
+              }
+            };
+            osparc.data.Resources.fetch("studies", "getOne", params)
+              .then(study => titleLabel.setValue(`You were notified in '${study["name"]}'`))
+              .catch(() => this.setEnabled(false));
+          }
+          if (userFromId) {
+            const user = osparc.store.Groups.getInstance().getUserByUserId(userFromId);
+            if (user) {
+              descriptionLabel.setValue(user.getLabel() + " wants you to check the conversation");
+            }
+          }
+          break;
         case "ANNOTATION_NOTE":
-          icon.setSource("@FontAwesome5Solid/file/14");
           if (resourceId) {
             const params = {
               url: {
@@ -204,28 +269,8 @@ qx.Class.define("osparc.notification.NotificationUI", {
           }
           break;
         case "WALLET_SHARED":
-          icon.setSource("@MaterialIcons/account_balance_wallet/14");
           break;
       }
-
-      const date = this.getChildControl("date");
-      notification.bind("date", date, "value", {
-        converter: value => {
-          if (value) {
-            return osparc.utils.Utils.formatDateAndTime(new Date(value));
-          }
-          return "";
-        }
-      });
-
-      const highlight = mouseOn => {
-        this.set({
-          backgroundColor: mouseOn ? "strong-main" : "transparent"
-        })
-      };
-      this.addListener("mouseover", () => highlight(true));
-      this.addListener("mouseout", () => highlight(false));
-      highlight(false);
     },
 
     __notificationTapped: function() {
@@ -250,6 +295,7 @@ qx.Class.define("osparc.notification.NotificationUI", {
           break;
         case "TEMPLATE_SHARED":
         case "STUDY_SHARED":
+        case "CONVERSATION_NOTIFICATION":
         case "ANNOTATION_NOTE":
           this.__openStudyDetails(resourceId, notification);
           break;
@@ -294,6 +340,9 @@ qx.Class.define("osparc.notification.NotificationUI", {
                 osparc.dashboard.ResourceBrowserBase.startStudyById(studyId, openCB);
               }
             });
+            if (notification.getCategory() === "CONVERSATION_NOTIFICATION") {
+              resourceDetails.addListener("pagesAdded", () => resourceDetails.openConversations());
+            }
           }
         })
         .catch(err => {
diff --git a/services/static-webserver/client/source/class/osparc/notification/Notifications.js b/services/static-webserver/client/source/class/osparc/notification/Notifications.js
index 2d5a2de9318..8ee9273958a 100644
--- a/services/static-webserver/client/source/class/osparc/notification/Notifications.js
+++ b/services/static-webserver/client/source/class/osparc/notification/Notifications.js
@@ -85,6 +85,21 @@ qx.Class.define("osparc.notification.Notifications", {
       };
     },
 
+    __newConversationNotificationObj: function(userId, studyId) {
+      const baseNotification = this.__newNotificationBase(userId);
+      const specNotification = {
+        "category": "CONVERSATION_NOTIFICATION",
+        "actionable_path": "study/"+studyId,
+        "resource_id": studyId,
+        "title": "New notification",
+        "text": "You were notified in a conversation"
+      };
+      return {
+        ...baseNotification,
+        ...specNotification
+      };
+    },
+
     __newAnnotationNoteObj: function(userId, studyId) {
       const baseNotification = this.__newNotificationBase(userId);
       const specNotification = {
@@ -122,7 +137,7 @@ qx.Class.define("osparc.notification.Notifications", {
       return osparc.data.Resources.fetch("notifications", "post", params);
     },
 
-    postNewStudy: function(userId, studyId) {
+    pushStudyShared: function(userId, studyId) {
       const params = {
         data: this.__newStudyObj(userId, studyId)
       };
@@ -136,7 +151,14 @@ qx.Class.define("osparc.notification.Notifications", {
       return osparc.data.Resources.fetch("notifications", "post", params);
     },
 
-    postNewAnnotationNote: function(userId, studyId) {
+    pushConversationNotification: function(userId, studyId) {
+      const params = {
+        data: this.__newConversationNotificationObj(userId, studyId)
+      };
+      return osparc.data.Resources.fetch("notifications", "post", params);
+    },
+
+    pushNewAnnotationNote: function(userId, studyId) {
       const params = {
         data: this.__newAnnotationNoteObj(userId, studyId)
       };
diff --git a/services/static-webserver/client/source/class/osparc/share/CollaboratorsStudy.js b/services/static-webserver/client/source/class/osparc/share/CollaboratorsStudy.js
index 124d275ae76..6be3a6b9884 100644
--- a/services/static-webserver/client/source/class/osparc/share/CollaboratorsStudy.js
+++ b/services/static-webserver/client/source/class/osparc/share/CollaboratorsStudy.js
@@ -217,7 +217,7 @@ qx.Class.define("osparc.share.CollaboratorsStudy", {
           const uid = potentialCollaborators[gid].getUserId();
           switch (this._resourceType) {
             case "study":
-              osparc.notification.Notifications.postNewStudy(uid, this._serializedDataCopy["uuid"]);
+              osparc.notification.Notifications.pushStudyShared(uid, this._serializedDataCopy["uuid"]);
               break;
             case "template":
             case "tutorial":
diff --git a/services/static-webserver/client/source/class/osparc/share/NewCollaboratorsManager.js b/services/static-webserver/client/source/class/osparc/share/NewCollaboratorsManager.js
index c8c21429d73..057cdfc1222 100644
--- a/services/static-webserver/client/source/class/osparc/share/NewCollaboratorsManager.js
+++ b/services/static-webserver/client/source/class/osparc/share/NewCollaboratorsManager.js
@@ -55,6 +55,14 @@ qx.Class.define("osparc.share.NewCollaboratorsManager", {
     "shareWithEmails": "qx.event.type.Data",
   },
 
+  properties: {
+    acceptOnlyOne: {
+      check: "Boolean",
+      init: false,
+      event: "changeAcceptOnlyOne"
+    }
+  },
+
   members: {
     __resourceData: null,
     __showOrganizations: null,
@@ -276,6 +284,7 @@ qx.Class.define("osparc.share.NewCollaboratorsManager", {
 
     __collaboratorButton: function(collaborator) {
       const collaboratorButton = new osparc.filter.CollaboratorToggleButton(collaborator);
+      collaborator.button = collaboratorButton;
       collaboratorButton.groupId = collaborator.getGroupId();
       collaboratorButton.subscribeToFilterGroup("collaboratorsManager");
 
@@ -298,6 +307,7 @@ qx.Class.define("osparc.share.NewCollaboratorsManager", {
       };
       const collaborator = qx.data.marshal.Json.createModel(collaboratorData);
       const collaboratorButton = new osparc.filter.CollaboratorToggleButton(collaborator);
+      collaborator.button = collaboratorButton;
       collaboratorButton.setIconSrc("@FontAwesome5Solid/envelope/14");
 
       collaboratorButton.addListener("changeValue", e => {
@@ -309,6 +319,11 @@ qx.Class.define("osparc.share.NewCollaboratorsManager", {
 
     __collaboratorSelected: function(selected, collaboratorGidOrEmail, collaborator, collaboratorButton) {
       if (selected) {
+        if (this.isAcceptOnlyOne() && Object.keys(this.__selectedCollaborators).length) {
+          // unselect the previous collaborator
+          const id = Object.keys(this.__selectedCollaborators)[0];
+          this.__selectedCollaborators[id].button.setValue(false);
+        }
         this.__selectedCollaborators[collaboratorGidOrEmail] = collaborator;
         collaboratorButton.unsubscribeToFilterGroup("collaboratorsManager");
       } else if (collaborator.getGroupId() in this.__selectedCollaborators) {
diff --git a/services/static-webserver/client/source/class/osparc/study/Conversations.js b/services/static-webserver/client/source/class/osparc/study/Conversations.js
index d43a945cf0c..720b00f7c99 100644
--- a/services/static-webserver/client/source/class/osparc/study/Conversations.js
+++ b/services/static-webserver/client/source/class/osparc/study/Conversations.js
@@ -93,6 +93,21 @@ qx.Class.define("osparc.study.Conversations", {
       return osparc.data.Resources.fetch("conversations", "addMessage", params)
         .catch(err => osparc.FlashMessenger.logError(err));
     },
+
+    notifyUser: function(studyId, conversationId, userGroupId) {
+      const params = {
+        url: {
+          studyId,
+          conversationId,
+        },
+        data: {
+          "content": userGroupId.toString(), // eventually the backend will accept integers
+          "type": "NOTIFICATION",
+        }
+      };
+      return osparc.data.Resources.fetch("conversations", "addMessage", params)
+        .catch(err => osparc.FlashMessenger.logError(err));
+    },
   },
 
   members: {
@@ -151,7 +166,7 @@ qx.Class.define("osparc.study.Conversations", {
       };
 
       if (conversations.length === 0) {
-        const noConversationTab = new osparc.info.Conversation(studyData);
+        const noConversationTab = new osparc.conversation.Conversation(studyData);
         conversationPages.push(noConversationTab);
         noConversationTab.setLabel(this.tr("new"));
         noConversationTab.addListener("conversationDeleted", () => reloadConversations());
@@ -159,7 +174,7 @@ qx.Class.define("osparc.study.Conversations", {
       } else {
         conversations.forEach(conversation => {
           const conversationId = conversation["conversationId"];
-          const conversationTab = new osparc.info.Conversation(studyData, conversationId);
+          const conversationTab = new osparc.conversation.Conversation(studyData, conversationId);
           conversationPages.push(conversationTab);
           conversationTab.setLabel(conversation["name"]);
           conversationTab.addListener("conversationDeleted", () => reloadConversations());
diff --git a/services/static-webserver/client/source/class/osparc/ui/window/Confirmation.js b/services/static-webserver/client/source/class/osparc/ui/window/Confirmation.js
index aafb1aac589..05cc501562f 100644
--- a/services/static-webserver/client/source/class/osparc/ui/window/Confirmation.js
+++ b/services/static-webserver/client/source/class/osparc/ui/window/Confirmation.js
@@ -40,7 +40,7 @@ qx.Class.define("osparc.ui.window.Confirmation", {
       check: [null, "create", "warning", "delete"],
       init: null,
       nullable: true,
-      apply: "__applyConfirmAppearance"
+      event: "changeConfirmAction",
     },
 
     confirmed: {
@@ -50,7 +50,6 @@ qx.Class.define("osparc.ui.window.Confirmation", {
   },
 
   members: {
-
     _createChildControlImpl: function(id) {
       let control;
       switch (id) {
@@ -64,6 +63,20 @@ qx.Class.define("osparc.ui.window.Confirmation", {
             this.setConfirmed(true);
             this.close(1);
           }, this);
+          this.bind("confirmAction", control, "appearance", {
+            converter: value => {
+              switch (value) {
+                case "create":
+                  return "strong-button";
+                case "warning":
+                  return "warning-button";
+                case "delete":
+                  return "danger-button";
+                default:
+                  return "strong-button";
+              }
+            }
+          });
           const command = new qx.ui.command.Command("Enter");
           control.setCommand(command);
           const btnsLayout = this.getChildControl("buttons-layout");
@@ -81,23 +94,5 @@ qx.Class.define("osparc.ui.window.Confirmation", {
     getCancelButton: function() {
       return this.getChildControl("cancel-button");
     },
-
-    __applyConfirmAppearance: function(confirmationAction) {
-      const confirmButton = this.getChildControl("confirm-button");
-      switch (confirmationAction) {
-        case "create":
-          confirmButton.setAppearance("strong-button");
-          break;
-        case "warning":
-          confirmButton.setAppearance("warning-button");
-          break;
-        case "delete":
-          confirmButton.setAppearance("danger-button");
-          break;
-        default:
-          confirmButton.resetAppearance();
-          break;
-      }
-    }
   }
 });
diff --git a/services/static-webserver/client/source/class/osparc/workbench/WorkbenchUI.js b/services/static-webserver/client/source/class/osparc/workbench/WorkbenchUI.js
index a9b633ed008..a4380c73195 100644
--- a/services/static-webserver/client/source/class/osparc/workbench/WorkbenchUI.js
+++ b/services/static-webserver/client/source/class/osparc/workbench/WorkbenchUI.js
@@ -1935,7 +1935,7 @@ qx.Class.define("osparc.workbench.WorkbenchUI", {
           serializeData.attributes.text = noteEditor.getNote();
           const user = osparc.store.Groups.getInstance().getUserByGroupId(gid)
           if (user) {
-            osparc.notification.Notifications.postNewAnnotationNote(user.getUserId(), this.getStudy().getUuid());
+            osparc.notification.Notifications.pushNewAnnotationNote(user.getUserId(), this.getStudy().getUuid());
           }
           this.__addAnnotation(serializeData);
           win.close();
diff --git a/services/web/server/src/simcore_service_webserver/api/v0/openapi.yaml b/services/web/server/src/simcore_service_webserver/api/v0/openapi.yaml
index d8e49bb3adf..db70d6dab52 100644
--- a/services/web/server/src/simcore_service_webserver/api/v0/openapi.yaml
+++ b/services/web/server/src/simcore_service_webserver/api/v0/openapi.yaml
@@ -13519,6 +13519,7 @@ components:
       - NEW_ORGANIZATION
       - STUDY_SHARED
       - TEMPLATE_SHARED
+      - CONVERSATION_NOTIFICATION
       - ANNOTATION_NOTE
       - WALLET_SHARED
       title: NotificationCategory
diff --git a/services/web/server/src/simcore_service_webserver/users/_notifications.py b/services/web/server/src/simcore_service_webserver/users/_notifications.py
index 68b322dc29c..37f902b0950 100644
--- a/services/web/server/src/simcore_service_webserver/users/_notifications.py
+++ b/services/web/server/src/simcore_service_webserver/users/_notifications.py
@@ -20,6 +20,7 @@ class NotificationCategory(StrAutoEnum):
     NEW_ORGANIZATION = auto()
     STUDY_SHARED = auto()
     TEMPLATE_SHARED = auto()
+    CONVERSATION_NOTIFICATION = auto()
     ANNOTATION_NOTE = auto()
     WALLET_SHARED = auto()
 
@@ -41,8 +42,7 @@ def category_to_upper(cls, value: str) -> str:
         return value.upper()
 
 
-class UserNotificationCreate(BaseUserNotification):
-    ...
+class UserNotificationCreate(BaseUserNotification): ...
 
 
 class UserNotificationPatch(BaseModel):
@@ -100,6 +100,19 @@ def create_from_request_data(
                     "product": "osparc",
                     "read": False,
                 },
+                {
+                    "id": "390053c9-3931-40e1-839f-585268f6fd3d",
+                    "user_id": "1",
+                    "category": "CONVERSATION_NOTIFICATION",
+                    "actionable_path": "study/27edd65c-b360-11ed-93d7-02420a000014",
+                    "title": "New notification",
+                    "text": "You were notified in a conversation",
+                    "date": "2023-02-23T16:28:13.122Z",
+                    "product": "s4l",
+                    "read": False,
+                    "resource_id": "3fb96d89-ff5d-4d27-b5aa-d20d46e20e12",
+                    "user_from_id": "2",
+                },
                 {
                     "id": "390053c9-3931-40e1-839f-585268f6fd3d",
                     "user_id": "1",