Using <!--@include: from page with frontmatter description breaks imported text

[Nicolai9852]

Describe the bug

I've experienced, that when rendering content from <!--@include: with a header, if the source had a frontmatter.description, it wouldn't import the correctly. It would either fail in the build or import the same header multiple times and/or text before the header.

Reproduction

1. Create two pages with some headers. Please also make some of the headers, some that are identical.
2. Create a frontmatter description on both pages (source page should be enough, but why not try both)
3. Use an to import the content from one page to another.
4. You should see, that it imports more that the selected header, either in plain text before the content or importing additional headers

Expected behavior

When using should only import the content below the heading.

System Info

System:
    OS: Windows 11 10.0.26200
    CPU: (16) x64 AMD Ryzen 7 5700X 8-Core Processor             
    Memory: 12.89 GB / 31.92 GB
  Binaries:
    Node: 26.2.0 - C:\Program Files\nodejs\node.EXE
    npm: 11.12.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: Chromium (144.0.3719.104)
    Firefox: 151.0.2 - C:\Program Files\Mozilla Firefox\firefox.exe
  npmPackages:
    vitepress: ^2.0.0-alpha.17 => 2.0.0-alpha.17

Additional context

I used GitHub Copilot trying to fix the issue. I ended up being successful by removing the !hasMeta in node_modules\vitepress\dist\node\chunk-CpMTk0EA.js

const atPresent = m1[0] === "@";
const includePath = atPresent ? path.join(srcDir, m1.slice(m1[1] === "/" ? 2 : 1)) : path.join(path.dirname(file), m1);
let content = fs__default.readFileSync(includePath, "utf-8");
+ if (path.extname(includePath) === ".md") {
+ content = matter(content).content;
+ }
if (region) {
      const [regionName] = region;
      const lines = content.split(/\r?\n/);

...

if (range) {
      const [, startLine, endLine] = range;
      const lines = content.split(/\r?\n/);
      content = lines.slice(
        startLine ? parseInt(startLine) - 1 : void 0,
        endLine ? parseInt(endLine) : void 0
      ).join("\n");
    }
- if (!hasMeta && path.extname(includePath) === ".md") {
- content = matter(content).content;
- }
    includes.push(slash(includePath));
    return processIncludes(
      md,
      srcDir,
      content,
      includePath,
      includes,
      cleanUrls
    );
  });
}

I've also found this issue, that is since long closed: #3195

Validations

• Check if you're on the latest VitePress version.
• Follow our Code of Conduct
• Read the docs.
• Check that there isn't already an issue that reports the same bug to avoid creating a duplicate.