diff --git a/manual/hack/02-source-code-fundamentals/10-comments.md b/manual/hack/02-source-code-fundamentals/10-comments.md
index f4f4e7e1d..46102025e 100644
--- a/manual/hack/02-source-code-fundamentals/10-comments.md
+++ b/manual/hack/02-source-code-fundamentals/10-comments.md
@@ -1,4 +1,4 @@
-# Comments
+.# Comments
 
 :::note
 Hash comments (`#`) are no longer supported, and are a parse error since [HHVM 4.133](https://hhvm.com/blog/2021/10/26/hhvm-4.133.html).