In Bug 351002 Firefox' download section was renamed. Thunderbird 2.0a1 / Seamonkey uses the same strings. We need to have own strings for Thunderbird / Seamonkey. These strings are affected: https://bugzilla.mozilla.org/attachment.cgi?id=236920
In Thunderbird we have the classic section "Attachments".
Those strings were removed in bug 395317 and replaced by a generic string pointing users to the Options dialog. See attachment 281730 [details] [diff] [review]: Reporter: is now the bug fixed?
This bug was fixed years ago - thanks.