New
"Reset to factory default" button in the admin->email settings
Once you have changed the default in admin->email setting, the default values are lost and if you have not copied them somewhere, you will rely on someone else (support? community?) to provide you with the info.
It would be so easy to have a "reset to default "button in this dialog:

Could be one button at the top, or event better, one button for each of the 4 zones.
-Greg