My configuration contains the equivalent of

(setopt org-agenda-files
       (directory-files-recursively "~/.local/share/org/todo" ".org$"))

My Emacs setup broke today due to the presence of a lockfile inside
"~/.local/share/org/todo".  I use EXWM, and I show org-agenda on startup:

(add-hook 'after-init-hook
            (lambda () (org-agenda nil "t")))
(setq initial-buffer-choice (lambda () (get-buffer "*Org Agenda*")))

org-agenda-files contained a non-existent file, so org-check-agenda-file
attempted to prompt me.  For some reason (maybe EXWM didn't fully load),
Emacs simply hung without prompting, leaving me with a black screen.

The attached patch silently removes lockfiles from org-agenda-files.

Thanks!

Joseph

P.S.

I'm not sure how the lockfile ended up there.  Maybe I killed Emacs with
SIGKILL while one of my agenda files was open and modified in a buffer,
and so the lockfile was not deleted?