Visualize web of trust with GPG 2.2.4 and sig2dot 0.35

Question

Following the answer from a previous question, I tried to do it myself, but sig2dot sends these error messages:

Use of uninitialized value $id in hash element at /usr/bin/sig2dot line 220, <> line 3.
Use of uninitialized value $id in hash element at /usr/bin/sig2dot line 224, <> line 3.
Use of uninitialized value $owner in string ne at /usr/bin/sig2dot line 242, <> line 6.
Use of uninitialized value $owner in hash element at /usr/bin/sig2dot line 243, <> line 6.
Use of uninitialized value $owner in string ne at /usr/bin/sig2dot line 246, <> line 6.

Then, dot gives a ps file, but it appears empty when opened with evince

GnuPG 2.2.4, sig2dot 0.35 in Ubuntu 18.04

Answer 1

bmhm's sig2dot solved this issue (partially): I cloned the git, and inside the directory where sig2dot.py is in, and used the example he gives, with the corresponding arguments.

For some keyrings, it won't link the signatures, so there are no arrows.