Since ver 0.9.9 I can't add recipients in the addressing area. Clicking the mouse into it only works the first time I compose a mail for every mailfolder. Composing a mail the next time in the same folder I can not see the cursor and the auto-expansion does not work. Strange. Adding recipients per addressbook-dialog works instead.
Which desktop manager are you using, KDE? maybe a dup of bug 130414
dup of 130581. Workarounds: a) use gnome b) activate another window and then reactivate the messahe compose window c) turn off the recycled compose window by adding the following line into your prefs.js file: pref("mail.compose.max_recycled_windows", 0); *** This bug has been marked as a duplicate of 130581 ***