[v3] fix not rendered default <meta name="description" /> and <meta property="og:description" /> (#3133)

* aa

* prettier

Author: dimaMachina

.changeset/light-bats-sin.md

@@ -0,0 +1,5 @@
+---
+'nextra-theme-docs': patch
+---
+
+fix not rendered default `<meta name="description" />` and `<meta property="og:description" />`

docs/pages/docs/guide/built-ins/filetree.mdx

@@ -23,7 +23,9 @@ Click the folder to test the dynamic functionality of the file tree.
 
 ## Usage
 
-Create the file tree structure by nesting `<FileTree.Folder>` and `<FileTree.File>` components within a `<FileTree>`. Name each file or folder with the `name` attribute. Use `defaultOpen` to set the folder to open on load.
+Create the file tree structure by nesting `<FileTree.Folder>` and
+`<FileTree.File>` components within a `<FileTree>`. Name each file or folder
+with the `name` attribute. Use `defaultOpen` to set the folder to open on load.
 
 ```mdx filename="MDX"
 import { FileTree } from 'nextra/components'

packages/nextra-theme-docs/src/constants.tsx

@@ -118,12 +118,11 @@ export const DEFAULT_THEME: DocsThemeConfig = {
       <>
         <title>{title}</title>
         <meta property="og:title" content={title} />
-        {description && (
-          <>
-            <meta name="description" content={description} />
-            <meta property="og:description" content={description} />
-          </>
-        )}
+        {/* We can't use React.Fragment https://nextjs.org/docs/pages/api-reference/components/head#use-minimal-nesting https://github.com/vercel/next.js/pull/67667 */}
+        {description && [
+          <meta key={0} name="description" content={description} />,
+          <meta key={1} property="og:description" content={description} />
+        ]}
         {canonical && <link rel="canonical" href={canonical} />}
         {image && <meta name="og:image" content={image} />}
       </>