User-agent:
Mozilla/5.0 (X11; Linux x86_64; rv:14.0) Gecko/20120714 Thunderbird/14.0
I noticed in the section on "passwords" in the Ubuntu Manual that the
Automatic Password Generator, that's built into Ubuntu, wasn't
mentioned. Just type "apg" into the terminal (no quotation marks) and
hit enter "apg" will do the rest.