[FIX] mail: fix crash when clicking a reply that is not yet loaded

closes odoo/odoo#78005

Signed-off-by: Sébastien Theys (seb) <seb@odoo.com>

addons/mail/static/src/models/message_in_reply_to_view/message_in_reply_to_view.js

@@ -36,6 +36,9 @@ function factory(dependencies) {
                 message: replace(parentMessage),
                 threadView: replace(threadView),
             });
+            if (!parentMessageView) {
+                return;
+            }
             threadView.addComponentHint('highlight-reply', parentMessageView);
         }