In reply to Demis's message of 29 Mar 2025:

I'll try to install gnome on VM.
To check.
But it won't be fast.
Try to look for errors in the message file (/var/log/messages).

Thank you, but don't bother too much, you have already done a lot.

Maybe it's necessary to modify other files, maybe /etc/resolv.conf (?)

I have to deeply study this matter.

Edit: now I'm in LXQT and all is the same (chromium doesn't start, the same error message when boinc manager starts). It seems something independent of the desktop. And as I said before, there are no error messages in the logs (/var/log directory)

Name resolution works fine for you.
You have already shown this above.
I think the problem is at the level of the graphics program.
This option can be checked by installing the cli console.

pkg search boinc_curses
boinc_curses-0.2.3_1           Console, ncurses based monitor and manager for BOINC

pkg install boinc_curses-0.2.3_1
Updating FreeBSD repository catalogue...
FreeBSD repository is up to date.
All repositories are up to date.
The following 1 package(s) will be affected (of 0 checked):

New packages to be INSTALLED:
        boinc_curses: 0.2.3_1

Number of packages to be installed: 1

110 KiB to be downloaded.

Proceed with this action? [y/N]: y
[1/1] Fetching boinc_curses-0.2.3_1.pkg: 100%  110 KiB 112.2kB/s    00:01
Checking integrity... done (0 conflicting)
[1/1] Installing boinc_curses-0.2.3_1...
[1/1] Extracting boinc_curses-0.2.3_1: 100%

cd /var/db/boinc
boinc_curses
(for exit press q, for help press h)

And if the console version works, then the problem is in the graphics part, perhaps just a problem with its settings.

ok.

The chromium and iridium problem when I change the hostname was fixed. It was only necessary to remove a lock file (SingletonLock -> x-2172), probably remaining because I rebooted the computer without closing the application. I've seen it's a thing that happens in GNU/Linux too.