diff --git a/qtribu/constants.py b/qtribu/constants.py
index c019654a..2b5a9b0d 100644
--- a/qtribu/constants.py
+++ b/qtribu/constants.py
@@ -230,3 +230,13 @@ def local_path(self, base_path: Path = Path().home() / ".geotribu/cdn/") -> Path
     CHEATCODE_10OCLOCK,
     CHEATCODE_QGIS_PRO_LICENSE,
 ]
+
+# QChat message types
+QCHAT_MESSAGE_TYPE_UNCOMPLIANT = "uncompliant"
+QCHAT_MESSAGE_TYPE_TEXT = "text"
+QCHAT_MESSAGE_TYPE_IMAGE = "image"
+QCHAT_MESSAGE_TYPE_NB_USERS = "nb_users"
+QCHAT_MESSAGE_TYPE_NEWCOMER = "newcomer"
+QCHAT_MESSAGE_TYPE_EXITER = "exiter"
+QCHAT_MESSAGE_TYPE_LIKE = "like"
+QCHAT_MESSAGE_TYPE_GEOJSON = "geojson"
diff --git a/qtribu/gui/dck_qchat.py b/qtribu/gui/dck_qchat.py
index 37c5e972..6dc66aa4 100644
--- a/qtribu/gui/dck_qchat.py
+++ b/qtribu/gui/dck_qchat.py
@@ -31,6 +31,11 @@
     CHEATCODE_IAMAROBOT,
     CHEATCODE_QGIS_PRO_LICENSE,
     CHEATCODES,
+    QCHAT_MESSAGE_TYPE_GEOJSON,
+    QCHAT_MESSAGE_TYPE_IMAGE,
+    QCHAT_MESSAGE_TYPE_LIKE,
+    QCHAT_MESSAGE_TYPE_NEWCOMER,
+    QCHAT_MESSAGE_TYPE_TEXT,
     QCHAT_NICKNAME_MINLENGTH,
 )
 from qtribu.gui.qchat_tree_widget_items import (
@@ -382,7 +387,7 @@ def on_ws_connected(self, room: str) -> None:
         # send newcomer message to websocket
         if not self.settings.qchat_incognito_mode:
             message = QChatNewcomerMessage(
-                type="newcomer", newcomer=self.settings.author_nickname
+                type=QCHAT_MESSAGE_TYPE_NEWCOMER, newcomer=self.settings.author_nickname
             )
             self.qchat_ws.send_message(message)
 
@@ -576,7 +581,7 @@ def on_like_message(self, liked_author: str, msg: str) -> None:
         This may happen on right-click on a message
         """
         message = QChatLikeMessage(
-            type="like",
+            type=QCHAT_MESSAGE_TYPE_LIKE,
             liker_author=self.settings.author_nickname,
             liked_author=liked_author,
             message=msg,
@@ -716,7 +721,10 @@ def on_send_button_clicked(self) -> None:
 
         # send message to websocket
         message = QChatTextMessage(
-            type="text", author=nickname, avatar=avatar, text=message_text.strip()
+            type=QCHAT_MESSAGE_TYPE_TEXT,
+            author=nickname,
+            avatar=avatar,
+            text=message_text.strip(),
         )
         self.qchat_ws.send_message(message)
         self.lne_message.setText("")
@@ -737,7 +745,7 @@ def on_send_image_button_clicked(self) -> None:
             with open(fp, "rb") as file:
                 data = file.read()
                 message = QChatImageMessage(
-                    type="image",
+                    type=QCHAT_MESSAGE_TYPE_IMAGE,
                     author=self.settings.author_nickname,
                     avatar=self.settings.author_avatar,
                     image_data=base64.b64encode(data).decode("utf-8"),
@@ -750,7 +758,7 @@ def on_send_screenshot_button_clicked(self) -> None:
         with open(sc_fp, "rb") as file:
             data = file.read()
             message = QChatImageMessage(
-                type="image",
+                type=QCHAT_MESSAGE_TYPE_IMAGE,
                 author=self.settings.author_nickname,
                 avatar=self.settings.author_avatar,
                 image_data=base64.b64encode(data).decode("utf-8"),
@@ -879,7 +887,7 @@ def on_send_layer_to_qchat(self) -> None:
         exporter.setTransformGeometries(True)
         geojson_str = exporter.exportFeatures(layer.getFeatures())
         message = QChatGeojsonMessage(
-            type="geojson",
+            type=QCHAT_MESSAGE_TYPE_GEOJSON,
             author=self.settings.author_nickname,
             avatar=self.settings.author_avatar,
             layer_name=layer.name(),
diff --git a/qtribu/logic/qchat_websocket.py b/qtribu/logic/qchat_websocket.py
index ba3928e1..d5613e07 100644
--- a/qtribu/logic/qchat_websocket.py
+++ b/qtribu/logic/qchat_websocket.py
@@ -3,8 +3,19 @@
 from json import JSONEncoder
 
 from PyQt5 import QtWebSockets  # noqa QGS103
+from qgis.core import Qgis
 from qgis.PyQt.QtCore import QObject, QUrl, pyqtSignal
 
+from qtribu.constants import (
+    QCHAT_MESSAGE_TYPE_EXITER,
+    QCHAT_MESSAGE_TYPE_GEOJSON,
+    QCHAT_MESSAGE_TYPE_IMAGE,
+    QCHAT_MESSAGE_TYPE_LIKE,
+    QCHAT_MESSAGE_TYPE_NB_USERS,
+    QCHAT_MESSAGE_TYPE_NEWCOMER,
+    QCHAT_MESSAGE_TYPE_TEXT,
+    QCHAT_MESSAGE_TYPE_UNCOMPLIANT,
+)
 from qtribu.logic.qchat_messages import (
     QChatExiterMessage,
     QChatGeojsonMessage,
@@ -97,20 +108,26 @@ def on_message_received(self, text: str) -> None:
         :param text: text message received, should be a jsonified string
         """
         message = json.loads(text)
+        if "type" not in message:
+            self.log(
+                message="No 'type' key in received message. Please make sure your configured instance is running gischat v>=2.0.0",
+                log_level=Qgis.Critical,
+            )
+            return
         msg_type = message["type"]
-        if msg_type == "uncompliant":
+        if msg_type == QCHAT_MESSAGE_TYPE_UNCOMPLIANT:
             self.uncompliant_message_received.emit(QChatUncompliantMessage(**message))
-        elif msg_type == "text":
+        elif msg_type == QCHAT_MESSAGE_TYPE_TEXT:
             self.text_message_received.emit(QChatTextMessage(**message))
-        elif msg_type == "image":
+        elif msg_type == QCHAT_MESSAGE_TYPE_IMAGE:
             self.image_message_received.emit(QChatImageMessage(**message))
-        elif msg_type == "nb_users":
+        elif msg_type == QCHAT_MESSAGE_TYPE_NB_USERS:
             self.nb_users_message_received.emit(QChatNbUsersMessage(**message))
-        elif msg_type == "newcomer":
+        elif msg_type == QCHAT_MESSAGE_TYPE_NEWCOMER:
             self.newcomer_message_received.emit(QChatNewcomerMessage(**message))
-        elif msg_type == "exiter":
+        elif msg_type == QCHAT_MESSAGE_TYPE_EXITER:
             self.exiter_message_received.emit(QChatExiterMessage(**message))
-        elif msg_type == "like":
+        elif msg_type == QCHAT_MESSAGE_TYPE_LIKE:
             self.like_message_received.emit(QChatLikeMessage(**message))
-        elif msg_type == "geojson":
+        elif msg_type == QCHAT_MESSAGE_TYPE_GEOJSON:
             self.geojson_message_received.emit(QChatGeojsonMessage(**message))