Excalibur-networkmanger-conf

Workaround applied as suggested by steve_v:
Result:

root@devuantest:~# ls -l /etc/NetworkManager/dispatcher.d/
total 16
-rwxr-xr-x 1 root root 2293 Nov  6 12:54 01-ifupdown
drwxr-xr-x 2 root root 4096 Jul 21 12:43 no-wait.d
drwxr-xr-x 2 root root 4096 Jul 21 12:43 pre-down.d
drwxr-xr-x 2 root root 4096 Jul 21 12:43 pre-up.d
root@devuantest:~#

andre@sapporo:~$ dpkg -l | grep -i network-manager
ii  network-manager                         1.52.1-1devuan1                      amd64        network management framework (daemon and userspace tools)
ii  network-manager-l10n                    1.52.1-1devuan1                      all          network management framework (translation files)

andre@sapporo:~$ uname -a
Linux sapporo 6.12.48+deb13-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.12.48-1 (2025-09-20) x86_64 GNU/Linux
andre@sapporo:~$ lsb_release -a
No LSB modules are available.
Distributor ID:	Devuan
Description:	Devuan GNU/Linux 6 (excalibur)
Release:	6
Codename:	excalibur
andre@sapporo:~$