How to Install the latest Mozilla Firefox version in Debian

These are the only two command that lets you install the latest Mozilla Firefox  Quantum on your Linux Debian

first download the latest Firefox version available

wget -O FirefoxSetup.tar.bz2 "https://download.mozilla.org/?product=firefox-latest&os=linux64&lang=en-US"

than create the directory

mkdir /opt/firefox

untar the latest Firefox version in the new directory

tar xjf FirefoxSetup.tar.bz2 -C /opt/firefox/

Optional:

Make a backup of the original Firefox binary shipped with Debian and create a new symbolic link pointing to downloaded Firefox executable:

mv /usr/lib/firefox-esr/firefox-esr /usr/lib/firefox-esr/firefox-esr_orig
ln -s /opt/firefox/firefox/firefox /usr/lib/firefox-esr/firefox-esr

Restore Debian’s Default

unlink /usr/lib/firefox-esr/firefox-esr
mv /usr/lib/firefox-esr/firefox-esr_orig /usr/lib/firefox-esr/firefox-esr

Thanks to Lubos Rendek