The minor mode is exactly the same as what you have in your previous email.
What actually happens in my regular setup is the key bindings in multiple
minor modes override the key map given to read-from-minibuffer. The problem
is I don't want to turn off those minor mode as they used to work in the
minibuffer in emacs 27 as intended, but not so in emacs 28.

One mode is smartparens and another is move-dup.

On Tue, 4 May 2021 at 3:29 pm Gregory Heytings <gregory@heytings.org> wrote:

>
> >> It's literally just a global minor mode defined for your test minor
> >> mode, basically `(define-global-minor-mode test-global-mode test-mode
> >> (lambda() t))`
> >
> > In that case, you should disable (or rather, not enable) that minor mode
> > for minibuffers, for example:
> >
> > (define-global-minor-mode test-global-mode test-mode (lambda () (or
> > (minibufferp) (test-mode 1))))
> >
>
> (Note that this does not answer your question "In Emacs 27, turning the
> minor mode on inside the minibuffer would not override the key map given
> to read-from-minibuffer", with the above the effect is the same in Emacs
> 27 and 28 AFAICS.  Without seeing the minor mode, I cannot help you more,
> I don't have a crystal ball.)
>
-- 
Jimmy Yuen Ho Wong