Sometimes when I open a message and read it is removed from the inbox and only seems to exist in the tab. When I close the tab the messages disappears from the inbox and is gone forever. I have lost quite a few important messages from this behav.ior. Most of the time when I open a message in the inbox it opens in a tab and then when I close the tab it remains in the inbox. I'm not sure when this happens, but when I open a message in a tab and it disappears from the inbox I do not know how to close the tab without permanently deleting the message.