File: /etc/apache2/conf-available/localized-error-pages.conf

    $ grep Order /etc/apache2/conf-available/localized-error-pages.conf
    #                               Order allow,deny

Please replace old Order allow,deny directives with Require like directives.

Quoting https://httpd.apache.org/docs/2.4/upgrading.html#run-time :

    In this example, there is no authentication and all requests are allowed.

    2.2 configuration:

        Order allow,deny
        Allow from all

    2.4 configuration:

        Require all granted

Therefore, the following is the upstream suggestion for this case:

--- a/etc/apache2/conf-available/localized-error-pages.conf	2024-09-29 18:51:28.000000000 +0000
+++ b/etc/apache2/conf-available/localized-error-pages.conf	2026-11-01 05:57:49.345473768 +0000
@@ -51,8 +51,7 @@
 #				Options IncludesNoExec
 #				AddOutputFilter Includes html
 #				AddHandler type-map var
-#				Order allow,deny
-#				Allow from all
+#				Require all granted
 #				LanguagePriority en cs de es fr it nl sv pt-br ro
 #				ForceLanguagePriority Prefer Fallback
 #			</Directory>

Hello,

Bug #1152743 in apache2 reported by you has been fixed in the
Git repository and is awaiting an upload. You can see the commit
message below and you can check the diff of the fix at:

https://salsa.debian.org/apache-team/apache2/-/commit/4b0df6c1fa79dae77130491858df39d9bc3be979
------------------------------------------------------------------------
Replace deprecated Order allow,deny / Allow from

Closes: #1152743
------------------------------------------------------------------------

(this message was generated automatically)
-- 
Greetings

https://bugs.debian.org/1152743