Plugin paperbuzz not loading metrics in OJS.3.1.2.4

Hi all,
I read other posts but I didn’t find a solution of this. I installed paperbuzz from Plugin Gallery and in debian installed libjs-d3 and libjs-d3-tip. On article page I have still “Metrics loading…” and nothing more.
What can I do with this ?

Linux 4.19.0-6-amd64 #1 SMP Debian 4.19.67-2+deb10u2 (2019-11-11) x86_64 GNU/Linux

  • Application Version - e.g., OJS 3.1.2.4
  • Theme bootstrap3

Regards, Paweł