docs: remove useless front matter (#7518)

website/docs/guides/markdown-features/markdown-features-admonitions.mdx

@@ -1,10 +1,11 @@
 ---
 id: admonitions
-title: Admonitions
 description: Handling admonitions/callouts in Docusaurus Markdown
 slug: /markdown-features/admonitions
 ---
 
+# Admonitions
+
 import BrowserWindow from '@site/src/components/BrowserWindow';
 import Tabs from '@theme/Tabs';
 import TabItem from '@theme/TabItem';

website/docs/guides/markdown-features/markdown-features-assets.mdx

@@ -1,10 +1,11 @@
 ---
 id: assets
-title: Assets
 description: Handling assets in Docusaurus Markdown
 slug: /markdown-features/assets
 ---
 
+# Assets
+
 import BrowserWindow from '@site/src/components/BrowserWindow';
 import Tabs from '@theme/Tabs';
 import TabItem from '@theme/TabItem';

website/docs/guides/markdown-features/markdown-features-code-blocks.mdx

@@ -1,10 +1,11 @@
 ---
 id: code-blocks
-title: Code blocks
 description: Handling code blocks in Docusaurus Markdown
 slug: /markdown-features/code-blocks
 ---
 
+# Code blocks
+
 import BrowserWindow from '@site/src/components/BrowserWindow';
 import CodeBlock from '@theme/CodeBlock';
 

website/docs/guides/markdown-features/markdown-features-head-metadata.mdx

@@ -1,6 +1,5 @@
 ---
 id: head-metadata
-title: Head Metadata
 description: Declaring page-specific head metadata through MDX
 slug: /markdown-features/head-metadata
 ---

website/docs/guides/markdown-features/markdown-features-intro.mdx

@@ -1,11 +1,11 @@
 ---
 id: introduction
-title: Markdown Features
-sidebar_label: Introduction
 description: Docusaurus uses MDX. Find out more about Docusaurus-specific features when writing Markdown.
 slug: /markdown-features
 ---
 
+# Markdown Features
+
 import BrowserWindow from '@site/src/components/BrowserWindow';
 
 Documentation is one of your product's interfaces with your users. A well-written and well-organized set of docs helps your users understand your product quickly. Our aligned goal here is to help your users find and understand the information they need, as quickly as possible.

website/docs/guides/markdown-features/markdown-features-math-equations.mdx

@@ -1,10 +1,11 @@
 ---
 id: math-equations
-title: Math Equations
 description: Writing LaTeX Math Equations
 slug: /markdown-features/math-equations
 ---
 
+# Math Equations
+
 import BrowserWindow from '@site/src/components/BrowserWindow';
 
 Mathematical equations can be rendered using [KaTeX](https://katex.org).

website/docs/guides/markdown-features/markdown-features-plugins.mdx

@@ -1,10 +1,11 @@
 ---
 id: plugins
-title: MDX Plugins
 description: Using MDX plugins to expand Docusaurus Markdown functionalities
 slug: /markdown-features/plugins
 ---
 
+# MDX Plugins
+
 Sometimes, you may want to extend or tweak your Markdown syntax. For example:
 
 - How do I embed youtube videos using the image syntax (`![](https://youtu.be/yKNxeF4KMsY)`)?

website/docs/guides/markdown-features/markdown-features-react.mdx

@@ -1,6 +1,5 @@
 ---
 id: react
-title: MDX and React
 description: Using the power of React in Docusaurus Markdown documents, thanks to MDX
 slug: /markdown-features/react
 ---

website/docs/guides/markdown-features/markdown-features-tabs.mdx

@@ -1,10 +1,11 @@
 ---
 id: tabs
-title: Tabs
 description: Using tabs inside Docusaurus Markdown
 slug: /markdown-features/tabs
 ---
 
+# Tabs
+
 ```mdx-code-block
 import BrowserWindow from '@site/src/components/BrowserWindow';
 import Tabs from '@theme/Tabs';