wicked_pdf: Error: PDF could not be generated! Command Error: Loading pages (1/6)

Issue description

I am running a rails 6 app, using last version of wicked_pdf (2.1.0) and wkhtmltopdf-binary (0.12.6.5).

I needed to reinstall everything because I installed a new SSD drive, so I wanted to start fresh, a clean and fresh install.

I installed everything, everything works fine until I got this

RuntimeError (Failed to execute:
["/home/tom/.rbenv/versions/2.6.3/gemsets/migrante-arc/bin/wkhtmltopdf", "--encoding", "UTF-8", "--lowquality", "file:////tmp/wicked_pdf20201111-111564-fn71lx.html", "/tmp/wicked_pdf_generated_file20201111-111564-9g9y4j.pdf"]
Error: PDF could not be generated!
 Command Error: Loading pages (1/6)
):=============================>                             ] 50%

If I run the command “outside” rails, it works, as described here: https://github.com/zakird/wkhtmltopdf_binary_gem/pull/99

I installed wkhtmltopdf from my distro repos (apt install wkhtmltopdf), in order to set exe_path: /usr/bin/wkhtmltopdf, and it works without any errors, as expected.

What am I missing? 😦

Expected or desired behavior

Get no errors (no RuntimeError)

System specifications

wicked_pdf gem version (output of cat Gemfile.lock | grep wicked_pdf):

     wicked_pdf (2.1.0)
  wicked_pdf

wkhtmltopdf version (output of wkhtmltopdf --version):

• using rbenv and ruby 2.6.3: wkhtmltopdf 0.12.6 (with patched qt)

• output from /usr/bin/wkhtmltopdf -- version (Debian unstable package version): wkhtmltopdf 0.12.6

whtmltopdf provider gem and version if one is used: wkhtmltopdf-binary 0.12.6.5

platform/distribution and version (e.g. Windows 10 / Ubuntu 16.04 / Heroku cedar): Debian unstable (sid)