Some function lookups using `helpful-function' yield `args-out-of-range' about helpful HOT 3 OPEN

It was tricky but I finally boiled it down to what it was, it is related to my setup and you can achieve it with the following steps:

1. M-: (setq debug-on-error t)
2. M-: (setq package-archives '(("gnu" . "https://elpa.gnu.org/packages/") ("melpa" . "https://melpa.org/packages/")))
3. M-x package-install org-mode
4. M-x package-install helpful
5. M-: (defun +is-useful-buffer (buffer) (not (string-match "^ ?\\*.*\\*\\(<[0-9]+>\\)?$" (buffer-name buffer))))
6. M-: (push '(buffer-predicate . +is-useful-buffer) default-frame-alist)
7. C-x 5 2
8. In the new frame run M-x helpful-function org-edit-special

So looking at this it is quite obvious since obviously the package expects some buffer with *...* to show up. I haven't experienced any issues with other things however with this buffer predicate (that I know of...)

Thank you for your help, perhaps I should look into alternatives to the buffer-predicate.

from helpful.

I'm unable to reproduce this with org-edit-special. Are you seeing it with other commands? Could you report your Emacs and org-mode versions, or better yet describe how to reproduce starting from emacs -Q?

from helpful.

Thanks, I can reproduce. I'm not sure what's causing it yet though.

from helpful.