layouts/PostLayout.js

@@ -51,6 +51,8 @@ export default function PostLayout({ children, frontMatter, next, prev }) {
                     <dl className="text-sm font-medium leading-5 whitespace-nowrap">
                       <dt className="sr-only">Name</dt>
                       <dd className="text-gray-900 dark:text-gray-100">{siteMetadata.author}</dd>
+                      {typeof siteMetadata.twitter === 'string' && (
+                        <>
                           <dt className="sr-only">Twitter</dt>
                           <dd>
                             <Link
@@ -60,6 +62,8 @@ export default function PostLayout({ children, frontMatter, next, prev }) {
                               {siteMetadata.twitter.replace('https://twitter.com/', '@')}
                             </Link>
                           </dd>
+                        </>
+                      )}
                     </dl>
                   </li>
                 </ul>