This is just a late response to the post #16 Rich2005:
viewtopic.php?f=9&t=17321&start=10#p237959
.... however never-ever been able to compile the voronoi plugin ...
Voronoi 2.2 compiled for Gimp 2.10.18/19 in (k)Ubuntu Eoan Ermine 19.10.
Unfortunately, the gradient "normal" selection is only for the Gimp-2.10.19 appimage version. Workaround "dragged and dropped" by Rich2005 is here:
https://www.gimp-forum.net/Thread-Tip-W ... 4#pid16994

Author:
David Necas "Yeti"

Sources:
http://web.archive.org/web/200501060422 ... s/voronoi/

Menu path:
Filters → Render → Pattern → Voronoi...

Doesn't work here.