Fix Bug: Multiple Copies of E-Mail when updating Inbox
When we send an E-Mail to 'ullimuelle@web.de' and press the update button at the bottom of the Inbox View before it arrives, the E-Mail appears multiple times in the Inbox. I tested it with sending the Mail to another E-Mail address (not the one we are logged in at) but only got one single mail. Maybe this is only a bug when sending an E-Mail to oneself? Some further testing is needed.