The argument is that the design is wrong.

Either icomplete-vertical-mode is a regular user option or icomplete-vertical-mode
should enable icomplete-mode too.

Many people would second this

Sincerely




From: Lars Ingebrigtsen <larsi@gnus.org>
To: arvid-harnack@lavache.com
Subject: bug#49075: (icomplete-vertical-mode 1) not taking effect
Date: 19/06/2021 15:34:58 Europe/Paris
Cc: 49075@debbugs.gnu.org

arvid-harnack@lavache.com writes:

> Recently, icomplete-vertical-mode was added. But calling
> (icomplete-vertical-mode 1) does not enable vertical completion,
> unless one has called (icomplete-mode 1) first.

I think that works as designed -- as the doc string says:

"Toggle vertical candidate display in `icomplete-mode' or `fido-mode'."

So the mode can't just switch on icomplete-mode by itself, because it
works two different modes.

Closing.

-- 
(domestic pets only, the antidote for overdose, milk.)
bloggy blog: http://lars.ingebrigtsen.no