diff --git a/addons/mail/static/src/js/utils.js b/addons/mail/static/src/js/utils.js
index 22e9a51b9dd..8ece5ef5040 100644
--- a/addons/mail/static/src/js/utils.js
+++ b/addons/mail/static/src/js/utils.js
@@ -92,6 +92,7 @@ function strip_html (node, transform_children) {
 
 function inline (node, transform_children) {
     if (node.nodeType === 3) return node.data;
+    if (node.nodeType === 8) return "";
     if (node.tagName === "BR") return " ";
     if (node.tagName.match(/^(A|P|DIV|PRE|BLOCKQUOTE)$/)) return transform_children();
     node.innerHTML = transform_children();