I need to import a very simple .csv list of email addresses into the Thunderbird address book. There's nothing else in the source file except email addresses. I go through the procedure to Import, and uncheck every field box except primary email address, and I can see the first email address on the right, then hit the button. It says import successful, but the address book is completely empty. Do I need to line up the email address on the right with the primary email address field on the left? I can't see a way to do that.