Incorrect page metadata when using markdown inline-code with XML tags inside

[SethFalco]

Have you read the Contributing Guidelines on issues?

• I have read the Contributing Guidelines on issues.

Prerequisites

• I'm using the latest version of Docusaurus.
• I have tried the npm run clear or yarn clear command.
• I have tried rm -rf node_modules yarn.lock package-lock.json and re-installing packages.
• I have tried creating a repro with https://new.docusaurus.io.
• I have read the console error message carefully (if applicable).

Description

Docusaurus doesn't correctly generate the metadata fields on pages when the first sentence of a page includes inline-code syntax with something that looks like an XML taga inside.

Example:

Removes the <metadata> element from the document.

Removes the [`<metadata>`](https://developer.mozilla.org/en-US/docs/Web/SVG/Element/metadata) element from the document.

Reproducible demo

https://github.com/SethFalco/metadata-sandbox

Steps to reproduce

1. Clone the repo
2. yarn install
3. yarn run build
4. Inspect build/docs/index.html

Expected behavior

They should be:

<meta data-rh="true" name="description" content="Removes the &lt;metadata&gt; element from the document.">

<meta data-rh="true" property="og:description" content="Removes the &lt;metadata&gt; element from the document.">

<p>Removes the <a href="https://developer.mozilla.org/en-US/docs/Web/SVG/Element/metadata" target="_blank" rel="noopener noreferrer" class=""><code>&lt;metadata&gt;</code></a> element from the document.</p>

Actual behavior

While the page itself renders correctly, the <metadata> nodes don't match what one would expect:

<meta data-rh="true" name="description" content="Removes the `` element from the document.">

<meta data-rh="true" property="og:description" content="Removes the `` element from the document.">

<p>Removes the <a href="https://developer.mozilla.org/en-US/docs/Web/SVG/Element/metadata" target="_blank" rel="noopener noreferrer" class=""><code>&lt;metadata&gt;</code></a> element from the document.</p>

Your environment

• Public source code: https://github.com/svg/svgo.dev
• Public site URL: https://svgo.dev
• Docusaurus version used: v3.9.2
• Environment name and version (e.g. Chrome 89, Node.js 16.4): Node.js v24.14.0
• Operating system and version (e.g. Ubuntu 20.04.2 LTS): Debian Trixie

Self-service

• I'd be willing to fix this bug myself.

---

Proposed Test Cases

packages/docusaurus-utils/src/__tests__/markdownUtils.test.ts

  it('creates excerpt with XML tag inside inline code', () => {
    expect(
      createExcerpt(dedent`
          # Markdown Regular Title

          This paragraph includes a link to the \`<metadata>\` documentation.
        `),
    ).toBe('This paragraph includes a link to the &lt;metadata&gt; documentation.');
  });

  it('creates excerpt with XML tag inside inline code with hyperlink', () => {
    expect(
      createExcerpt(dedent`
          # Markdown Regular Title

          This paragraph includes a link to the [\`<metadata>\`](https://developer.mozilla.org/en-US/docs/Web/SVG/Element/metadata) documentation.
        `),
    ).toBe('This paragraph includes a link to the &lt;metadata&gt; documentation.');
  });

Results (truncated):

 FAIL  packages/docusaurus-utils/src/__tests__/markdownUtils.test.ts
  ● createExcerpt › creates excerpt with XML tag inside inline code

    Expected: "This paragraph includes a link to the <metadata> documentation."
    Received: "This paragraph includes a link to the `` documentation."

  ● createExcerpt › creates excerpt with XML tag inside inline code with hyperlink

    Expected: "This paragraph includes a link to the <metadata> documentation."
    Received: "This paragraph includes a link to the `` documentation."