diff --git a/lib/socket/socket.react.js b/lib/socket/socket.react.js
--- a/lib/socket/socket.react.js
+++ b/lib/socket/socket.react.js
@@ -12,6 +12,7 @@
 import MessageHandler from './message-handler.react.js';
 import RequestResponseHandler from './request-response-handler.react.js';
 import UpdateHandler from './update-handler.react.js';
+import UserInfosHandler from './user-infos-handler.react.js';
 import { updateActivityActionTypes } from '../actions/activity-actions.js';
 import { updateLastCommunicatedPlatformDetailsActionType } from '../actions/device-actions.js';
 import {
@@ -366,6 +367,10 @@
           frozen={this.props.frozen}
           keyserverID={this.props.keyserverID}
         />
+        <UserInfosHandler
+          addListener={this.addListener}
+          removeListener={this.removeListener}
+        />
       </React.Fragment>
     );
   }
diff --git a/lib/socket/user-infos-handler.react.js b/lib/socket/user-infos-handler.react.js
new file mode 100644
--- /dev/null
+++ b/lib/socket/user-infos-handler.react.js
@@ -0,0 +1,37 @@
+// @flow
+import * as React from 'react';
+import { useEffect } from 'react';
+
+import {
+  type SocketListener,
+  type ClientServerSocketMessage,
+} from '../types/socket-types.js';
+import { serverServerSocketMessageValidator } from '../types/socket-types.js';
+import { extractUserIDsFromPayload } from '../utils/conversion-utils.js';
+
+type Props = {
+  +addListener: (listener: SocketListener) => void,
+  +removeListener: (listener: SocketListener) => void,
+};
+
+export default function UserInfosHandler(props: Props): React.Node {
+  const { addListener, removeListener } = props;
+
+  const onMessage = React.useCallback((message: ClientServerSocketMessage) => {
+    // eslint-disable-next-line no-unused-vars
+    const newUserIDs = extractUserIDsFromPayload(
+      serverServerSocketMessageValidator,
+      message,
+    );
+    // TODO: dispatch an action adding the new user ids to the UserStore
+  }, []);
+
+  useEffect(() => {
+    addListener(onMessage);
+    return () => {
+      removeListener(onMessage);
+    };
+  }, [addListener, removeListener, onMessage]);
+
+  return null;
+}