Description of problem:
I normally display unread messages only, but can use the menu to switch to displaying all messages. After updating to Thunderbird final, the menu option (View?) where this is possible appeared to be missing. On closer inspection, I find that I can click on the menu bar to the left of "Go", where it turns out there are several menu options that are "hidden", but each of them has a full menu below it.
Version-Release number of selected component (if applicable):
The unlabeled menu items are File, Edit, and View.
I think it's due to my having thunderbird-lightning installed. Under Tools/Add-ons/Extensions, it showed that "Provider for Google Calendar" was not supported by Thunderbird 3, but after reinstalling thunderbird-lightning, I was able to get that error message to go away, and now the three hidden menu options show up normally. So this was probably never a thunderbird bug. Closing as NOTABUG. Sorry.
*** This bug has been marked as a duplicate of bug 542736 ***