Lisp error: (wrong-type-argument number-or-marker-p nil)
Hmm that's quite curious... I can reproduce it also without my change
in 56537ab0228, FWIW. AFAICT the issue is that icomplete trims the
prefix from completion candidates before passing them to
completion-lazy-hilit, while completion--hilit-from-re expects the full
candidate (prefix included). I'm not deeply familiar with icomplete,
but maybe calling completion-lazy-hilit before trimming the candidates
as in the diff below should do the trick?