The Same Procedure with only some Little changes will Work also on Debian 5 Lenny and 7 Wheezy.
The Guide Includes the Basic Screenshots of Process to Make the Visualization Easier.
Is Important you Take the Time to Carefuly Reading and Following the Instructions Contained in this Guide.
Download Latest Thunderbird for LinuxThunderbird 68 i686 tar.bz2
Double-Click on Archive to Extract
Open a Terminal Window
(Press “Enter” to Execute Commands)
Relocate Thunderbird Latest
Login as SuperUser
If Got “User is Not in Sudoers file” then see: How to Enable sudo
sudo chown -R root:root /tmp/thunderbird && mv /tmp/thunderbird /opt
Make a Thunderbird Symlink for Easy-Starting
ln -s /opt/thunderbird/thunderbird /usr/bin/thunderbird
Next you Can Start Thunderbird from Terminal with
Create a Thunderbird Launcher for Easy&Quick Starting:How Launcher for Debian Lxde
How to Install the Latest Firefox on Debian Linux: