1 files changed, 5 insertions, 1 deletions
diff --git a/addons/mail/static/src/models/thread/thread.js b/addons/mail/static/src/models/thread/thread.js
index 6eaed09ad8b..5304130345e 100644
--- a/addons/mail/static/src/models/thread/thread.js
+++ b/addons/mail/static/src/models/thread/thread.js
@@ -561,7 +561,11 @@ function factory(dependencies) {
                 return;
             }
             this.update({ pendingSeenMessageId: messageId });
-            return this.env.models['mail.thread'].performRpcChannelSeen({ ids: [this.id], lastMessageId: messageId });
+            return this.env.models['mail.thread'].performRpcChannelSeen({
+                ids: [this.id],
+                // commands have fake message id that is not integer
+                lastMessageId: Math.floor(messageId),
+            });
         }
 
         /**