📝 Overview

Thorium Reader opens PDF files beautifully, but Windows doesn’t let users select it in "Open with" in Files Explorer or set it as the default app for .pdf files.
This limitation exists because Thorium doesn’t declare .pdf as a supported file extension in its app manifest.

❗ Problem

• Thorium Reader cannot be selected in "Open with" or "Default apps" for PDF files.
• PDF support appears incomplete, even though it functions well.
• Users face friction when trying to use Thorium as their primary PDF viewer.

💡 Suggested Solution

• Add .pdf to the list of supported file extensions in Thorium Reader’s app manifest.

🎯 Expected Outcome

• Thorium Reader will appear in Windows’ file association settings.
• Users will be able to:
  • Choose Thorium Reader in "Open with"
  • Set it as their default PDF viewer if desired

📌 Benefits

• Enhances user experience and flexibility
• Aligns perceived functionality with actual capabilities
• Encourages adoption by users seeking a reliable PDF reader