Subject: 28.0.50; undefined entry on M-S-x in org-mode

From: Gabriel do Nascimento Ribeiro <[email-masked]>
Date: Sat, 20 Feb 2021 15:25:55 -0300

Steps:
- emacs -Q
- change to some buffer in org-mode
- press M-S-X
- there is an `undefined` entry in the Completions list