Run pw3270 inside firejail

[raelschiffler]

Have anyone tried running this application inside a firejail sandbox?
I'm stuck in a GTK error:

(base) user@10:44 AM:$ sudo firejail --private-bin=pw3270 --join-network=2310
/etc/sudoers.d/defaults:2:4: syntax error

^
Switching to pid 2311, the first child process inside the sandbox
Child process initialized in 0.75 ms
root@user:/home/user# OPENSSL_CONF=/.config/opensslTLSv1.cnf pw3270
GLib-GIO _g_io_module_get_default: Found default implementation dconf (DConfSettingsBackend) for ‘gsettings-backend’
gtk Loading plugins from /usr/lib/pw3270/5.4/plugins

(pw3270:8909): dconf-WARNING **: 10:45:18.694: failed to commit changes to dconf: Error spawning command line “dbus-launch --autolaunch=13da9b9ba4b64ddebab4fcc2387bfa6d --binary-syntax --close-stderr”: Child process exited with code 1
Authorization required, but no authorization protocol specified

(pw3270:8909): Gtk-WARNING **: 10:45:18.697: cannot open display: :0

I'm using '--private-bin=pw3270' because otherwise it wouldn't find the bin.
'--join-network=2310' is because I need the application to run inside a network namespace already set by firejail.

Environment explanation:
Debian 11, firejail was primarily run with --interface=eno1 with the intention of moving the network interface into a new network namespace, making it not available to the operational system. This is the first created sandbox.
Running pw3270 in a new firejail sandbox using '--join-network' parameter, I create another sandbox sharing the same network namespace created before, using as parameter value the first sandbox's PID.

Any question, I'm happy to explain and contribute.

[PerryWerneck]

I dont know firejail but, based on the error message (cannot open display: :0) seens like the access to GUI is blocked. It's a firejail issue (maybee needs more configuration) not related with pw3270 itself.