User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8a4) Gecko/20040927 Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8a4) Gecko/20040927 This appears to be a new problem in 1.8 alpha 4 which I just upgraded to today: When changing to a different mail folder, if the selected message in the folder I'm moving to has a long "To" or "CC" list, which is expanded out to show all members in the area between the message list and message body, it displays with a *LOT* of extra space beneath it. Reproducible: Always Steps to Reproduce: 1. Receive a mail with a long 'CC' list 2. Put that message in a folder 3. Move to the new folder. 4. Expand the 'CC' list. All is well so far. 5. Move back to your inbox. 6. Finally click on the folder containing the message again. Actual Results: The 'cc' list area is enormous with a large amount of wasted space beneath. Expected Results: Should just display the CC list, expanded, with the correct sized window pane. Screenshot of problem available at: http://ij.mine.nu/****/mozilla18a4-mail-error.png
Appears to be a dupe of, or at least very similar to, bug 262875. The screenshot you posted apparently has the CC: header label scribbled out, but there doesn't appear to be a twisty for it, altho there is for the To: Does toggling the twisty make the space disappear?
I did do a good number of bug searches but found no dups myself. Sorry. This does look like the same issue, I guess. The mail I screenshotted doesn't have a 'CC' at all (oops) but this happens with long "To" lists, too, which is what I grabbed. Yes, clicking the twisty so the list size reduces, removes the extra space, and it doesn't come back, either. It only appears when moving to a new folder WITH an expanded list.
*** This bug has been marked as a duplicate of 255201 ***