Minibuffer keymap issue?

Aloha,

I'm on latest Arch Linux, Emacs 30.2.

Here is an MWE:

(defun rjnfoo (foo-string)
  (interactive "sfoo-string: ")
  )

Calling this, or anything that uses minibuffer-local-keymap,
interprets capital 'C' as ctrl-C.  I can correct this with

(keymap-set minibuffer-local-map "C" 'self-insert-command)

I would have liked to research this further but
minibuffer-local-map is defined in C source code.

I cannot find anything in my startup files that define C as
ctrl-C in minibuffer-local-map in my startup files.  I could
of course easily be wrong.

Has anyone else seen this and/or can verify this behavior?  If
not, it's obviously my problem.

Mahalo,

-- 
Bob Newell
Honolulu, Hawai`i

- Via GNU-Linux/Emacs/Gnus/BBDB