Thunderbird - Show all email addresses

Solution 1:

Someone did find a hack to enable something like this, but it seems like it could be more hassle than it's worth (and may not even work in the latest versions).

See this thread: http://forums.mozillazine.org/viewtopic.php?f=39&t=546398

You may want to add this as an idea at http://getsatisfaction.com/mozilla_messaging if it's not already there.

Solution 2:

mail.showCondensedAddresses is the one

Solution 3:

Since Thunderbird 3.1.3 (circa 2010), the following property allows you to choose the default number of address lines shown before "more" appears:

mailnews.headers.show_n_lines_before_more

When equal to 0 all lines are shown. It defaults to 1. (Reference.)