During Kara's conversation with Alex in her apartment, Kara's hair keeps switching from hanging along her back to being draped in front of her shoulders.
When the bank robbers' getaway car smashes into Supergirl, the passenger side air bag deploys. The action immediately following this collision does not show the air bag.
When Winn searches for Promethium, the chemical symbol C12H22O11 is displayed on his screen. C12H22O11 is the chemical symbol for various disaccharides, including table sugar.
When Cat is introducing Kara to her new boss, the phone on Cat's desk does not have a phone line or a power cord plugged into it.
Clark Kent refers to the president as a he but it has been established on this earth, the POTUS is a woman.