• https://www.mozilla.org/ru/firefox/download/thanks/

• Make Chrome trust the Linux system certificate store or select certificates via policies

client1# apt install -y p11-kit p11-kit-modules

client1# ln -s -f /usr/lib/x86_64-linux-gnu/pkcs11/p11-kit-trust.so /usr/lib/firefox-esr/libnssckbi.so

• A user.js file is an alternative method of modifying preferences
• How to Change Firefox Proxy Settings Programmatically?
• Переменные окружения
• Автоматизация использования SQUID

server# FIREFOX_USER=user2

debian# FIREFOX_PROFILE_FOLDER=/home/${FIREFOX_USER}/.mozilla/firefox/$(grep 'Path.*esr' /home/${FIREFOX_USER}/.mozilla/firefox/profiles.ini | cut -d'=' -f2)
alt# FIREFOX_PROFILE_FOLDER=/home/${FIREFOX_USER}/.mozilla/firefox/$(grep 'Path.*default-default' /home/${FIREFOX_USER}/.mozilla/firefox/profiles.ini | cut -d'=' -f2)

server# cat ${FIREFOX_PROFILE_FOLDER}/user.js

user_pref("network.proxy.http", "gate");
user_pref("network.proxy.http_port", 3128);
user_pref("network.proxy.ssl", "gate");
user_pref("network.proxy.ssl_port", 3128);
user_pref("network.proxy.no_proxies_on", "localhost,127.0.0.1,isp.un,corpX.un");
user_pref("network.proxy.type", 1);

chown ${FIREFOX_USER}:${FIREFOX_USER} ${FIREFOX_PROFILE_FOLDER}/user.js

Помогает:

about:config

network.auth.use-sspi;false