The canonical source for this seems to be
"https://sites.math.washington.edu/~palmieri/Emacs/
That file says
"This hasn't been updated in a while, and it is not likely to be
updated any time soon."
The last file revision is 2005.
This bug has been open for 8 years with no progress, and seems to make
highlight-completion unusable.
Therefore this file should be removed from emacs-goodies-el before the
next stable release.
d