Hello Carlos and Eli,

The fix for bug#37782 in commit e3cebbb (2019-10-19) introduced an error
when starting emacsclient.

    undefined: KEY must be an integer, cons, symbol, or string

I think the message is from keymap.c around line 2279.

This error is reproducible and is happening on FreeBSD (versions 12.0
and 12.1 confirmed).

Regards,

Joseph