How to start LO 6.3 without avahi-daemon or disable dbus.

Hi!
I recently upgraded LO to 6.3 on my Ubuntu 18.04 (Kernel 4.15.0-58).
Everything is fine, but I found a severe issue for me. I work in a small school in Peru and we have a pc in every classroom, that means that many people can access the pc, even the students (they need to). For this reason I have to limit some functionalities to maintain sanity in the network and in the same machines, one of this limits is to disable dbus in avahi-daemon.conf.
Avahi is a very nice tool because it permits a lot of automatic configurations (printers, network and so on), but in certain environments, like mine, is a real danger because permits access everywhere without control.
Now, if I disable dbus in avahi-daemon.conf I can configure only the external resources I want the pc can access to and everything on the linux box keep working fine, but LO Calc doesn’t: it keep 30-45 seconds to load a simple sheet (writer, draw, impress, doesn’t have this issue), that is strange because if I open Calc without calling a sheet the program open the main window in 2 seconds.
Furthermore in all the LO modules the printer window need 60-75 seconds to open, that happen only in LO, others tools I have installed on the pc have no problems.
There is some tuning I can do to override this problem?
Thanks a lot.

Luca

ok, I got a radical solution, I removed avahi-daemon from my pc, some people think that is not a good idea because something can crash.
Until now everything is working, LO works fine, no more delays or lags.