arp(8) and "blackhole" keyword

From: Marek Zarychta <zarychtam_at_plan-b.pwste.edu.pl>
Date: Fri, 11 Jun 2021 18:58:39 UTC
Dear subscribers,

is arp(8) still supposed to honour the "blackhole" keyword with the -S
option? Does it also apply to fast-forwarded packets like those
forwarded by 13-STABLE stack?
I suppose the "blackhole" keyword is not in transition to anything like
"blockhole" yet, since it seems to be not recognizable by arp(8).

Best regards,
-- 
Marek Zarychta