Sugestão de sources.list para o Debian 10 (Buster)

Após entrar no terminal como root

#mousepad /etc/apt/sources.list

Copiar o conteúdo abaixo

#------------------------------------------------------------------------------#
# OFFICIAL DEBIAN REPOS
#------------------------------------------------------------------------------#

###### Debian Main Repos
deb http://ftp.br.debian.org/debian/ buster main contrib non-free
#deb-src http://ftp.br.debian.org/debian/ buster main contrib non-free

deb http://ftp.br.debian.org/debian/ buster-updates main contrib non-free
#deb-src http://ftp.br.debian.org/debian/ buster-updates main contrib non-free

deb http://security.debian.org/ buster/updates main
#deb-src http://security.debian.org/ buster/updates main

#deb http://ftp.debian.org/debian buster-backports main
#deb-src http://ftp.debian.org/debian buster-backports main