Thanks foar your answer but I know this article too. Thats's why I wrote "installed via snap store...."
If you do so, you won't have this domoticz.sh
Here a Output from the described directory:
$ cd /etc/init.d/
mqtt@lip-smart-01:/etc/init.d$ ls -l
total 132
-rwxr-xr-x 1 root root 3740 Apr 1 2020 apparmor
-rwxr-xr-x 1 root root 2964 Dec 6 2019 apport
-rwxr-xr-x 1 root root 1071 Jul 24 2018 atd
-rwxr-xr-x 1 root root 1232 Mar 27 2020 console-setup.sh
-rwxr-xr-x 1 root root 3059 Feb 11 2020 cron
-rwxr-xr-x 1 root root 937 Feb 4 2020 cryptdisks
-rwxr-xr-x 1 root root 896 Feb 4 2020 cryptdisks-early
-rwxr-xr-x 1 root root 3152 Sep 30 2019 dbus
-rwxr-xr-x 1 root root 985 Nov 13 00:15 grub-common
-rwxr-xr-x 1 root root 3809 Jul 28 2019 hwclock.sh
-rwxr-xr-x 1 root root 2638 Dec 13 2019 irqbalance
-rwxr-xr-x 1 root root 1503 May 11 2020 iscsid
-rwxr-xr-x 1 root root 1479 Nov 27 2019 keyboard-setup.sh
-rwxr-xr-x 1 root root 2044 Feb 19 2020 kmod
-rwxr-xr-x 1 root root 695 Jan 28 2020 lvm2
-rwxr-xr-x 1 root root 586 Jan 28 2020 lvm2-lvmpolld
-rwxr-xr-x 1 root root 3323 Mar 3 2020 mosquitto
-rwxr-xr-x 1 root root 2827 Jan 9 2020 multipath-tools
-rwxr-xr-x 1 root root 2503 May 11 2020 open-iscsi
-rwxr-xr-x 1 root root 1846 Mar 9 2020 open-vm-tools
-rwxr-xr-x 1 root root 1366 Mar 23 2020 plymouth
-rwxr-xr-x 1 root root 752 Mar 23 2020 plymouth-log
-rwxr-xr-x 1 root root 924 Feb 13 2020 procps
-rwxr-xr-x 1 root root 4417 Oct 15 2019 rsync
-rwxr-xr-x 1 root root 2864 Mar 7 2019 rsyslog
-rwxr-xr-x 1 root root 1222 Apr 3 2017 screen-cleanup
-rwxr-xr-x 1 root root 3939 May 29 2020 ssh
-rwxr-xr-x 1 root root 6872 Apr 22 2020 udev
-rwxr-xr-x 1 root root 2083 Jan 21 2020 ufw
-rwxr-xr-x 1 root root 1391 Apr 14 2020 unattended-upgrades
-rwxr-xr-x 1 root root 1306 Apr 2 2020 uuidd
root@lip-smart-01:~# find / -name domoticz.sh
root@lip-smart-01:~#
NOTHING FOUND ON MY SYSTEM