Hello,

I'm experiencing a problem with Zotero's built-in PDF reader on Windows.

After accidentally upgrading to Zotero 10, Zotero started freezing whenever I tried to add comments to highlighted text in PDFs.

I initially used WebDAV for file syncing, then switched back to Zotero storage, but the freezing continued.

I subsequently deleted my Zotero data folder and reinstalled Zotero 9.0.5.

Since then, whenever I open a PDF in Zotero, the PDF reader displays a completely blank tab.

Here is what I've tested:

My bibliographic references are still visible in Zotero.

The PDF files open normally in external PDF readers.

Even newly imported PDFs display blank tabs.

Restarting Zotero in Troubleshooting Mode does not resolve the issue.

Report ID: 982781179

Debug ID: D1662736703

Could you help me identify the cause and restore the built-in PDF reader without losing my existing annotations?

Thank you very much!