LibreSign cannot open file – "URL du document introuvable" with negative file_id

[matwebdev1982-commits]

Describe the bug

LibreSign fails to open a valid PDF file from the Files interface, showing "URL du document introuvable", while logs indicate an incorrect negative file_id is used.

To reproduce

Reproduction steps:

1. Upload a PDF file
2. Select the file
3. Click "Open in LibreSign"
4. Error appears

Observed behavior:

• LibreSign fails to load the document
• Same behavior:
• in private browsing
• via public share link
• Nextcloud preview works correctly

Logs:

LibreSign API call shows a negative file_id:

GET /ocs/v2.php/apps/libresign/api/v1/file/validate/file_id/-368864

This seems incorrect (file_id should not be negative).

Expected behavior:
LibreSign should load the document normally using a valid file_id.

Expected behavior

No response

Screenshots

No response

Environment information

Environment:

Nextcloud Hub 26 (33.0.2.2)
LibreSign 13.2.0
Nginx
Ubuntu server
PHP CLI working

Dependencies:

OpenSSL ✔ configured
Poppler ✔ installed
PDFtk ✔ working
JSignPdf ✔ working

(All checks are green in LibreSign configuration panel)

Additional context

Additional checks performed:

• Internal HTTP access OK (curl from server works)
• No missing DB indices
• Tested with multiple browsers
• Tested with public link → same issue