I noticed the graphviz bugs in 2.39 or newer related to rendering overly long arrows have not moved forward at all:
http://www.graphviz.org/mantisbt/view.php?id=2607
http://www.graphviz.org/mantisbt/view.php?id=2608
Meanwhile, there's activity with graphviz issues in their new source repo location here: https://gitlab.com/graphviz/graphviz/issues
It might be worth a shot to report those bugs as gitlab issues?
Cheers!