Rear hangs in the initramfs build step, and continues if process cfg3html is killed

Issue

• The rear process hangs at the Collecting general system information step:

  ++ Log 'Collecting general system information (cfg2html)'
  ++ test 1 -gt 0
  +++ Stamp
  +++ date '+%Y-%m-%d %H:%M:%S '
  ++ echo '2020-04-27 11:45:45 Collecting general system information (cfg2html)'
  2020-04-27 11:45:45 Collecting general system information (cfg2html)
  ++ mkdir -p -v -m0750 /var/lib/rear/recovery/cfg2html
  ++ StopIfError 'Could not create '\''/var/lib/rear/recovery/cfg2html'\'' directory'
  ++ ((  0 != 0  ))
  ++ cfg2html -p -o /var/lib/rear/recovery/cfg2html
  

• We can see with ps that some process are running:

  root     15722 11047  0 13:43 pts/6    00:00:00 /bin/bash /usr/sbin/rear -v mkrescue
  root     15726 15722  0 13:43 pts/6    00:00:00 /bin/bash /usr/bin/cfg2html-linux -p -o /var/lib/rear/recovery/cfg2html -x -A -P
  root     26109 15726  0 13:43 pts/6    00:00:00 /bin/bash /usr/bin/cfg2html-linux -p -o /var/lib/rear/recovery/cfg2html -x -A -P
  root     26110 26109  0 13:43 pts/6    00:00:00 /bin/bash /usr/bin/cfg2html-linux -p -o /var/lib/rear/recovery/cfg2html -x -A -P