Hi Pedro,
Orbeon Forms can insert a handwritten signature in a PDF template, and you
can see this in with the W-9 form on
https://demo.orbeon.com (click to open
the form on the link in bottom left of the page, then Review, then PDF). The
field you create for the image is just like any other text field. Orbeon
Forms just uses the Acrobat Form Field to know where you'd like you'd like
to insert the signature, so I don't see a reason why you wouldn't be able to
create it with LibreOffice.
https://doc.orbeon.com/form-builder/advanced/pdf-production/pdf-templates#image-attachments
I also attached a PDF for the W-9 form, so you can maybe see how the field
is done for the signature.
w9.pdf <
http://discuss.orbeon.com/file/t119778/w9.pdf>
You'll let me know if you manage to make it work, or still encounter some
problem with this.
-Alex
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