Thunderbird bug or feature?

[Bruno Wolff III]

On Thu, Jun 18, 2009 at 16:42:06 -0700,
  Konstantin Svist <fry.kun at gmail.com> wrote:
> 
> In 1-to-1 emails, though, this quickly becomes annoying since emails go
> back and forward a lot and you'd need to scroll down more and more to
> read each successive messages. It makes sense to leave the original
> thread at the bottom in case CCed readers join in in the middle and for
> general reference/sanity checks (which email is this one a reply to?).

You're supposed to trim the messages.
There are a few prominent posters on the Fedora lists that don't trim
posts and reading their replies is more difficult than it should be.