Unexpected code block rendering when pasting raw HTML without backticks #931
Description
Initial checklist
- I read the support docs
- I read the contributing guide
- I agree to follow the code of conduct
- I searched issues and discussions and couldn’t find anything (or linked relevant results below)
Affected package
Steps to reproduce
Steps to reproduce
When passing raw HTML (not wrapped in a code block) to React Markdown without any properties set, part of it is incorrectly rendered as a code block.
Please open the v0 app.
v0 app to reproduce the behavior of react-markdown
https://v0.app/chat/markdown-preview-app-dOrDi7YXj29?ref=6BRKSK
input text
Do not include triple backticks when pasting
<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>サンプルページ</title>
<style>
body {
font-family: Arial, Helvetica, sans-serif;
line-height: 1.6;
margin: 0;
padding: 0 16px;
background-color: #f9f9f9;
color: #333;
}
header {
background-color: #4a90e2;
color: white;
padding: 24px 0;
text-align: center;
margin-bottom: 16px;
}
nav {
margin: 16px 0;
display: flex;
gap: 12px;
}
nav a {
text-decoration: none;
color: #333;
padding: 8px 12px;
border-radius: 4px;
background: #fff;
border: 1px solid #ddd;
}
nav a:hover {
background: #f0f0f0;
}
main {
max-width: 800px;
margin: 0 auto;
background: #fff;
padding: 20px;
border-radius: 6px;
box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}
footer {
text-align: center;
color: #777;
padding: 20px 0;
margin-top: 20px;
}
.hero {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 20px;
align-items: center;
}
.hero img {
max-width: 100%;
border-radius: 6px;
}
@media (max-width: 700px) {
.hero {
grid-template-columns: 1fr;
}
}
</style>
</head>
<body>
<header>
<h1>ようこそ、サンプル HTML ページへ</h1>
<p>このページは基本的な HTML の構造を示すだけのサンプルです。</p>
</header>
<nav aria-label="ナビゲーション">
<a href="#section1">セクション1</a>
<a href="#section2">セクション2</a>
<a href="#section3">セクション3</a>
</nav>
<main>
<section id="section1" class="hero">
<div>
<h2>セクション1</h2>
<p>これはサンプルの段落です。HTML の要素を組み合わせてページを作成します。</p>
<ul>
<li>リスト項目1</li>
<li>リスト項目2</li>
<li>リスト項目3</li>
</ul>
</div>
<div>
<img src="https://via.placeholder.com/350x200" alt="ダミー画像" />
</div>
</section>
<section id="section2">
<h2>セクション2</h2>
<p>リンクの例：</p>
<p>
ダミーリンク: <a href="https://example.com" target="_blank" rel="noopener">https://example.com</a>
</p>
<p>テーブルは後で追加することもできます。</p>
</section>
<section id="section3">
<h2>セクション3</h2>
<p>フォームの例は以下のようになります。実際には送信は行いません。</p>
<form action="#" method="post" aria-label="サンプルフォーム">
<label for="name">名前:</label><br />
<input type="text" id="name" name="name" placeholder="例: 太郎" /><br /><br />
<label for="email">メールアドレス:</label><br />
<input type="email" id="email" name="email" placeholder="[email protected]" /><br /><br />
<input type="submit" value="送信" />
</form>
</section>
</main>
<footer>
<p>© 2025 サンプルサイト</p>
</footer>
</body>
</html>
Actual behavior
HTML that is not wrapped in a code block is not displayed as-is.
Expected behavior
HTML that is not wrapped in a code block should be output as-is, without being converted into a code block.
Runtime
Package manager
Operating system
macOS
Build and bundle tools
Next.js