You probably have a bug filed on messages in the mail window not displaying the header info already... There is an additional problem where, when that happens, if you try to click on the grippy to collapse and re-expand the message pane (to try to get the header info to draw), the header info draws properly but then you can't select/view any more messages in that folder. ...In other words: STEPS TO REPRODUCE: 1) Switch to a folder with unread messages, open one of them. 2) The header info for that message should theoretically display, but doesn't. 3) Click on the grippy to collapse the message pane, click it again to re-expand it. 4) The header info should now display. 5) Try to click on other messages in the folder, to view them. It doesn't work. You have to switch to a different folder and come back to view other messages. Note also that if you do not attempt to force the header info to display, this problem does not appear. This is reproducable always, on all platforms, since the mailnews branch landing.
The problem about the header envelope not displaying is bug 39655. I'm changing the summary of this bug to reflect the selection problem after snapping the message pane shut/open.
Steps 1+2 seem like a dup of the bug mention but the rest of the steps describe this bug which I am also able to reproduce. I thought we had a bug on this but I couldn't find it. So, marking nsbeta1+
*** Bug 74989 has been marked as a duplicate of this bug. ***
Re-assigning to varada
Adding Eric Vaughan to the bug. This behaviour is happening because the splitter is not throwing back proper state values.i.e. open when closed and vice versa.
OK using apr17 commercial trunk build: linux rh6.2, win98, mac OS 9.0