1 files changed, 2 insertions, 2 deletions
diff --git a/addons/mail/static/src/components/thread_preview/thread_preview.js b/addons/mail/static/src/components/thread_preview/thread_preview.js
index b10e8ee2586..92fcb6101d1 100644
--- a/addons/mail/static/src/components/thread_preview/thread_preview.js
+++ b/addons/mail/static/src/components/thread_preview/thread_preview.js
@@ -108,8 +108,8 @@ class ThreadPreview extends Component {
      * @param {MouseEvent} ev
      */
     _onClickMarkAsRead(ev) {
-        if (this.thread.lastMessage) {
-            this.thread.markAsSeen(this.thread.lastMessage.id);
+        if (this.thread.lastNonTransientMessage) {
+            this.thread.markAsSeen(this.thread.lastNonTransientMessage);
         }
     }