Hi gnu/emacs!
Thanks a lot for the quick reply I got. I have tried out both:
(setq query-replace-read-from-default (lambda () ""))
and the 
(setq query-replace-read-from-default (lambda () (make-string 0 32)))
Unfortunately the irritating (default FROM -> TO) still shows...I also did try to read and follow the code but limited in LISP knowledge and I didn't find anything which I didn't already try.
It is rather strange a simple disable variable was missed to implement.
This show another aspect of the problem with the current and rather strange implementation:https://emacs.stackexchange.com/questions/19844/how-to-cancel-the-default-in-replace-string
It is like emacs is leaving the unix way to keep things simple.
/Regards Niclas Olsson, Sweden
    Den torsdag 24 april 2025 kl. 18:13:43 CEST, Manuel Giraud <manuel@ledu-giraud.fr> skrev:  
 
 Niclas Olsson via "Bug reports for GNU Emacs, the Swiss army knife of
text editors" <bug-gnu-emacs@gnu.org> writes:

> Hi gnu/emacs,

[...]

> I have tried all setq on the:

[...]

Hi,

It seems that setting the following does what you want:

(setq query-replace-read-from-default (lambda () ""))

I found this by reading the code since it is not a well documented
custom.  Maybe, we should have one (?)
-- 
Manuel Giraud