I think this preference is the one you want: mailnews.emptyTrash.dontAskAgain Select and copy (ctrl+c) that line above. # Now, go to '''[http://kb.mozillazine.org/Menu_differences_in_Windows,_Linux,_and_Mac Tools|Options]|Advanced|General→Config Editor''' # Click the button. If prompted, promise to be careful. # Paste from your clipboard into the search box at the top. # If this preference already exists, it should appear now. You can right-click it and toggle it to the alternative value. You need it set to '''false'''. # If the preference doesn't exist, right-click in the lower window, select '''New''', then '''Boolean''', then paste in the name from the clipboard, and set it to '''false'''. Note there is a similar preference for mailnews.emptyJunk.dontAskAgain which may also be of interest to you.

This works. Thank you.