diff --git a/src/components/listItem.tsx b/src/components/listItem.tsx
index 1e4f9c2..cd0eaf4 100644
--- a/src/components/listItem.tsx
+++ b/src/components/listItem.tsx
@@ -45,7 +45,7 @@ export function ListItem({
   line?: number;
   children?: any[];
 }): JSX.Element {
-  if (checked === undefined) {
+  if (checked == null) {
     return (
       <li>
         <MyST ast={children} />