fix(embed): strip front matter from included markdown

[sy-records]

Summary

Related issue, if any:

Close #2654

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

For any code change,

• Related documentation has been updated, if needed
• Related tests have been added or updated, if needed

Does this PR introduce a breaking change?

• Yes
• No

Tested in the following browsers:

• Chrome
• Firefox
• Safari
• Edge

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Project	Deployment	Actions	Updated (UTC)
docsify-preview	Ready	Preview, Comment	Jul 7, 2026 7:32am

[paulhibbitts]

Thanks very much @sy-records ! I was unsure how to duplicate this issue on Codesandbox, so I used the provided PR preview and screenshots from the originating issue.

I reviewed the original PR and confirmed the issue is on the most recent RC.4 release:
https://preview.docsifyjs.org/#/embed-files

Looking at the PR preview, I can confirm that the included Markdown is now stripped and is not included in the rendered Sidebar:
https://docsify-preview-git-fork-sy-records-fix-front-matter-docsifyjs.vercel.app/preview/#/embed-files