Thunderbird continues to delete my trash and inbox emails. I have tried multiple times to adjust the settings through those individual folders, but it does not seem to work. I've tried going to Tools>Account Settings>Synchronization & Storage>Disc Space where I changed the setting to never delete. Unfortunately, the SAVE box does not show on my screen so I'm assuming that is the problem. How do I get the SAVE box to show so I can save my settings.