diff --git a/src/components/atoms/MarkdownPreviewer.tsx b/src/components/atoms/MarkdownPreviewer.tsx
index ccdbdd6d35..e3648c4663 100644
--- a/src/components/atoms/MarkdownPreviewer.tsx
+++ b/src/components/atoms/MarkdownPreviewer.tsx
@@ -114,6 +114,8 @@ function rehypeCodeMirrorAttacher(options: Partial<RehypeCodeMirrorOptions>) {
           })
         } else if (!ignoreMissing) {
           throw new Error(`Unknown language: \`${lang}\` is not registered`)
+        } else {
+          return;
         }
       }