Hmm, no, I am using emacs 27 and assumed this wouldn't work as I wasn't aware of this behavior. So, the minibuffer-messages are queued then? Well, interesting. I must say it wasn't really apparent from the minibuffer-message doc. It would be great if a note could be added there.

Anyway, thanks for taking the time to understand my problem.

06.10.2020, 14:06, "Eli Zaretskii" <eliz@gnu.org>:

From: pinkanon pinkanon <pinkanon.pinkanon@yandex.com>
Cc: "43813@debbugs.gnu.org" <43813@debbugs.gnu.org>
Date: Tue, 06 Oct 2020 14:01:10 +0300

Here's an example:

;; someone else's code (minibuffer-message "important message") // flycheck, whatever
;; ...
;; my code soon after:
;; (unless (current-message) (minibuffer-message "unimportant info"))
echo area: "unimportant info" instead of "important info"

When I run this, I first see "important message" displayed for 2 sec,
then "unimportant message" is displayed. So no important message
seems to be overwritten.

Are you doing this in Emacs 27?