RE: [External] : who's setting value of kill-emacs-query-functions

[Drew Adams]

> kill-emacs-query-functions is a variable defined in ‘files.el’.
> 
> Its value is (server-kill-emacs-query-function desktop-kill)
> Original value was nil

See that "Original value was nil"?

Bisect your init file to find the culprit.
You can use command `comment-region' to
comment a selection of code (e.g. lines).
(`C-u' uncomments instead).

Comment out 1/2, then 3/4, 7/8, 15/16,
31/32,... till you find the responsible
code.  That's a binary search - quick.

(You can also `M-x grep' the code of the
packages you use, for `desktop-kill' or
`kill-emacs-query-functions', for example.)