Origami::InvalidPDFError: No trailer found, in pdf.sign() when using pdf file (v1.5)

[yvonnenieuwerth]

We generated a version 1.5 pdf file, which can be 'read' by origami, but as soon as we try to 'sign' and save it, we get the following error:

 Origami::InvalidPDFError:
       No trailer found
     # /Users/yvonne/.rvm/gems/ruby-2.5.1/gems/origami-2.1.0/lib/origami/trailer.rb:47:in `trailer'
     # /Users/yvonne/.rvm/gems/ruby-2.5.1/gems/origami-2.1.0/lib/origami/pdf.rb:809:in `output'
     # /Users/yvonne/.rvm/gems/ruby-2.5.1/gems/origami-2.1.0/lib/origami/pdf.rb:223:in `save'

Without the 'sign' method, the save works fine. We also tried it with pdf version 1.4, and that seems to work fine also. The pdf files are generated by princexml.

The pdf file used: pdf_to_sign.pdf

It might be related to issue #16 , but the error message is different, and also said to be fixed in an earlier version.

[nogdacosta]

Is there any update on this issue?