"Khelp module "ertt" can't unload until its refcount drops from 1 to 0." after "All buffers synced."?

From: Mark Millard via freebsd-current <freebsd-current_at_freebsd.org>
Date: Wed, 17 Nov 2021 20:13:18 UTC
I've not noticed the ertt message before in:

. . .
Waiting (max 60 seconds) for system thread `bufspacedaemon-1' to stop... done
All buffers synced.
Uptime: 1d9h57m18s
Khelp module "ertt" can't unload until its refcount drops from 1 to 0.



===
Mark Millard
marklmi at yahoo.com
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