thunderbird: howto copy mail headers

[Johannes Wiedersich <johannes@physik.blm.tu-muenchen.de>]

I have recently turned too stupid to be able to select and copy the 
headers from emails in order to paste them elsewhere. With the mouse I 
can select only a single line of header information at a time, but I 
would like to copy the whole message: all headers plus body text.

Is this still possible with less than 10 mouse clicks?

Thanks, Johannes