sign on pdf existing ?

              sign_digital:
                '#type': webform_signature
                '#title': 'Affidavit: I swear or affirm that'
                '#states':
                  visible:
                    ':input[name="sign"]':
                      value: digital
                  required:
                    ':input[name="sign"]':
                      value: digital

The webform module provides a field of type "webform_signature" , you can use this field value to get the image with the signature.

For other signing logic you can make a reusable form handler using drush gen and select it from the webform settings user interface.

https://git.drupalcode.org/project/webform_sign_pdf_example/-/blob/1.0.x...

and

https://git.drupalcode.org/project/webform_sign_pdf_example/-/blob/1.0.x...

Here's a good explanation

https://www.jrockowitz.com/blog/voter-registration

Alternatively:

• https://www.drupal.org/project/signature_pad →
• https://www.drupal.org/project/signature_field →
• https://www.drupal.org/project/signaturefield →

ah I see, you use html to create a template and print it to pdf. My case is more complicated, the customer uploaded an existing pdf file and I had to insert an digital signature + image signature. The problem is that when I use fpdi to insert images, it can only work with the old pdf version 1.4. The new pdf files have compression mode so fpdi cannot load them. I dont if you have another free library