>
> The following diff should fix this bug, could you please test it?
>
> diff --git a/lisp/completion-preview.el b/lisp/completion-preview.el
> index 4928d9a8824..eb4b9111b30 100644
> --- a/lisp/completion-preview.el
> +++ b/lisp/completion-preview.el
> @@ -520,6 +520,7 @@ completion-preview-complete
>              ;; hook update the completion preview in case the candidate
>              ;; can be completed further.
>              (when (functionp efn)
> +              (completion-preview-active-mode -1)
>                (funcall efn (concat base com) (if (cdr all) 'exact
> 'finished)))
>            ;; Otherwise, remove the common prefix from the preview.
>            (completion-preview--inhibit-update)
>
>
>
> Regards,
>
> Eshel
>

Hi Eshel,

 I applied this patch to my emacs-30.1 source tree and I can confirm that
it fixes the issue. Thank you for addressing this so quickly!

Vincent