Stability and fallbacks with uncaught exception exists in HTML

[mathetos]

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• I've searched for any related issues and avoided creating a duplicate issue.

Please give us a description of what happened

When a post or page contains HTML that causes the League HTML-to-Markdown converter to throw, the plugin does not catch the exception. The request fails with a fatal error (500) instead of returning markdown or a safe fallback, so the .md URL breaks instead of degrading gracefully.

To Reproduce

Step-by-step reproduction instructions

1. Create or edit a post that includes HTML that triggers the League HTML-to-Markdown converter to throw (e.g., certain malformed structures, edge-case markup, or content that exposes bugs in the converter).
2. Visit the post’s .md URL (e.g. https://yoursite.com/post-slug.md).
3. The request fails with a PHP fatal error / 500 response instead of returning markdown.

Expected results

1. The .md URL returns valid output (markdown or a plain-text fallback) instead of crashing.

Actual results

1. The request throws an uncaught exception and returns a 500 error or PHP fatal error.

Technical info

• If relevant, which editor is affected (or editors):

• Block Editor
• Gutenberg Editor
• Elementor Editor
• Classic Editor
• Other:

• Which browser is affected (or browsers):

• Chrome
• Firefox
• Safari
• Other:

Used versions

• Device you are using: web/Chrome
• Operating system: Windows 11
• PHP version: 8.3
• WordPress version: 6.9.1
• WordPress Theme: 2025
• Plugin version: 1.0.0
• Relevant plugins in case of a bug: