When we go to Region & Language menu to change locale (language and units) of a newly installed system with GNOME, may not have the language you are looking for. For the most cases is a question of enable it on /etc/locale.gen.

For this, just edit the file /etc/locale.gen with root privileges:

$ sudo vim /etc/locale.gen

And uncomment the language that you looking for, e.g:

for

#pt_BR.UTF-8 UTF-8

remove the #, and save

pt_BR.UTF-8 UTF-8

After edit the locale file, regenerate locales with command:

sudo locale-gen

That's it! Just go to Region & Language and select your language.

referencies:

Gnome (Debian 11): How to install en*DK formats (date, numbers, units)?: https://unix.stackexchange.com/questions/679315/gnome-debian-11-how-to-install-en-dk-formats-date-numbers-units [_archive*]

This problem consists of black background insted the wallpaper on xfce4, apparently is the xfdesktop daemon that was not starting on login. To fix it, wee just need to setup this daemon to auto start on login:

1. Go to Session and Startup > Application Autostart
2. Then click on Add
3. Will appear a window, enter some name, like "Wallpaper Daemon" and the description, "Daemon to load the xfce4 wallpaper", on the command field, add the command xfdesktop --replace.
4. After save the config, restart the computer.

references:

Desktop background appears black when using XFCE: https://unix.stackexchange.com/questions/151471/desktop-background-appears-black-when-using-xfce [archive]