1. Download Thunderbird 2. (Save to disk)
2. sudo tar -C /opt -zxvf ~/Desktop/thunderbird-*
3. sudo ln -s /opt/thunderbird/thunderbird /usr/local/bin/thunderbird
4. create a menu item: sudo gedit /usr/share/applications/thunderbird.desktop
[Desktop Entry]
Encoding=UTF-8
Name=Thunderbird
Comment=Thunderbird Mail Client
Exec=thunderbird
Icon=/opt/thunderbird/icons/mozicon16.xpm
StartupNotify=true
Terminal=false
Type=Application
Categories=Applications;Network