diff --git a/_includes/footer.html b/_includes/footer.html
index 14f6db9a10..56518ac49f 100644
--- a/_includes/footer.html
+++ b/_includes/footer.html
@@ -20,11 +20,13 @@
{% comment %}
Inject Twitter widgets asynchronously. Snippet snipped from Twitter's
JS interface site: https://dev.twitter.com/docs/tfw-javascript
+
+ * "js.async=1;" added to add async attribute to the generated script tag.
{% endcomment %}