Visible signature coordinates saved as (0,0,0,0) → results in invisible signature (jsignpdf engine).

[EtherGhost]

Describe the bug

When placing a visible signature box in LibreSign and saving the document, the signature element is stored in the database with zero coordinates: llx = 0 lly = 0 urx = 0 ury = 0.

To reproduce

1. Upload a PDF (tested with: LibreOffice-exported PDF or scanned PDF)
2. Open the document in LibreSign
3. Add a signer
4. Place a visible signature box on the page
5. Click Save
6. (Optional) Re-open the document → signature box is not visible
7. Send and sign the document
8. Download the signed PDF
9. SELECT * FROM oc_libresign_file_element WHERE file_id = ; =>
   type: signature
   page: 1
   llx: 0
   lly: 0
   urx: 0
   ury: 0

Expected behavior

• Signature box coordinates should be saved correctly in DB and visible signature should appear in the signed PDF

Screenshots

No response

Environment information

Nextcloud version: 33.0.0
Installation type: HanssonIT prebuilt Nextcloud server
LibreSign version: 13.2.0
PHP version: 8.3.6
Browser: Firefox 148.0.2 (64-bit)
Signature engine: jsignpdf
JSignPdf version: 2.3.0 (bundled)

Additional context

Workaround:
Manually updating coordinates in DB fixes the issue:

UPDATE oc_libresign_file_element
SET llx = 100, lly = 100, urx = 250, ury = 180
WHERE id = <element_id>;

Additional Notes:
QR code rendering works correctly → PDF modification pipeline is functional
Signature is cryptographically valid
Issue occurs consistently (100% reproducible)
Happens with different PDF types
Appears to be related to UI → backend coordinate persistence

Related Behavior (Native Engine)
When switching to native signature engine:

Could not sign PDF using native v1 engine.
Root cause: Failed to inflate FlateDecode stream.

Additional detail:

The signature box is placed using the mouse in the UI (drag and resize),
and appears correctly positioned before saving.

After clicking "Save":

• UI reports success
• but coordinates are stored as 0,0,0,0 in database

This happens consistently regardless of:

• PDF type (LibreOffice export, scanned PDF)
• user

This suggests the issue occurs during the UI → backend save step,
not during PDF processing or signing.

[qix67]

I am new to libresign and I have exactly the same error.

I run a gentoo + nginx, nextcloud 32.0.5, php 8.3.29, libresign 12.4.0 with jsign. My web browser is vivaldi.

The problem seems to occurs when saving signature box position. libresign/api/v1/request-signature is called with 0 for nearly all positions and size.

[ciaens]

Please see: #7316
For the patch: #7316 (comment) or #7317

[gnfranco]

Confirming this bug

I can confirm this issue on a different environment. The visible signature drawing is never rendered in the signed PDF — only the QR code appears.

Environment:

• Nextcloud version: 33.0.0 (self-hosted, Ubuntu)
• LibreSign version: 13.2.0
• PHP version: 8.3
• Signature engine: JSignPdf 2.3.0 (bundled via occ libresign:install)
• Java: OpenJDK 21.0.8 LTS
• PDFtk: 3.3.3
• Browser: tested on Chrome and Firefox
• Signer type: external user (email token, no Nextcloud account)

Behavior observed:

1. Admin places a visible signature box on the PDF page in the UI
2. UI reports success on save
3. External signer receives email link, draws signature on canvas and confirms
4. Signed PDF is returned — QR code appears correctly in the footer, but the drawn signature image is completely absent
5. Digital/cryptographic signature IS valid — only the visual rendering is missing
6. Confirmed via DB: coordinates stored as llx=0 lly=0 urx=0 ury=0

Additional notes:

• QR code renders correctly, confirming the JSignPdf pipeline itself is functional
• Issue is 100% reproducible regardless of PDF type or signer
• The drawn signature canvas image appears to be collected in the browser but not transmitted or persisted correctly to the backend before signing

The DB workaround described in this issue (manually setting coordinates) partially helps with positioning, but the drawn image itself still does not appear in the final PDF.

Happy to provide logs or test specific patches if that helps move this forward.

[nlublovary]

Hi, I just noticed the same today, colleagues told me that signatures no longer appear. After setting the position of a signature, saving and then re-editing the position again, the box is gone, as if it was not saved at all, not even at 0,0 position.

This is a major bug to us and renders this 13.2.0 useless. I had to roll back to 13.1.3 and with that version is works fine.

Thanks.